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*Department of Biology, Centenary College of Louisiana, Shreveport, LA 71105; and Departments of Molecular and Cellular Physiology and Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71105
Submitted July 7, 2008; Revised August 31, 2008; Accepted September 18, 2008
Monitoring Editor: Robin Wright
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ABSTRACT |
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INTRODUCTION |
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Here, we report a semester-long research project that requires students to use bioinformatics tools to design and interpret a molecular biology-based experiment investigating structural determinants of protein kinase activity. Our goals for the course were to allow students to experience the excitement and challenges of original research while increasing their ability to understand and use the tools of the modern molecular biologist. Our specific learning objectives were as follows:
The results from a knowledge survey administered at the beginning and end of the semester indicate that learning objectives 1 and 2 were met, whereas assessment of lab reports over the course of the semester indicated that objective 3 was met. In addition, student perceptions of the project indicate that they felt the process facilitated their learning.
Background for the Research Project
This project focuses on casein kinase 1 (CK1) protein kinases, using the yeast enzyme Yck2 as a model CK1. The CK1 subfamily of protein kinases comprises a diverse group of kinases found in all eukaryotic cells. CK1 protein kinases from multicellular organisms regulate processes, including synaptic transmission (Faundez and Kelly, 2000), receptor signaling (Tobin et al., 1997), circadian rhythm (Lee et al., 2001), DNA repair (Knippschild et al., 1997), nuclear import (Vielhaber et al., 2000), and cell division (Brockman et al., 1992). CK1 activities also have been implicated with roles in neurodegenerative diseases, including Alzheimer's disease, and could be involved in a variety of cancers (Schwab et al., 2000; Rubinfeld et al., 2001). CK1 enzymes phosphorylate Ser or Thr residues C-terminal to acidic residues. The classical site for CK1 is Asp/Glu-X-X-Ser/Thr (Tuazon and Traugh, 1991), but it has been demonstrated that P
Ser/PThr-X-X-Ser/Thr provides high-affinity CK1 recognition for the downstream Ser/Thr residue (Flotow and Roach, 1989).
Yck2 together with Yck1 forms a pair of essential and redundant kinases in the budding yeast Saccharomyces cerevisiae (Robinson et al., 1993; Vancura et al., 1993). The Yck proteins are essential for cell division and viability, and in addition to other functions, they seem to be involved in membrane protein turnover, bud site selection, polarization of the actin cytoskeleton, and function of the septin ring that is essential for cytokinesis in yeast (Robinson et al., 1993; Panek et al., 1997; Robinson et al., 1999; Marchal et al., 2002). In accord with functions at the plasma membrane, Yck2 was found to be a peripheral membrane protein of approximately 62 kDa (Vancura et al., 1993). Yck2 is anchored to the membrane via palmitoylation of its two terminal cysteine residues (Roth et al., 2002; Babu et al., 2004). Targeting to the plasma membrane (as opposed to internal membranes) requires the 48 C-terminal residues that seem to be required solely for palmitoylation (Babu et al., 2004).
We used a previously generated green fluorescent protein (GFP)-tagged YCK2 clone and two yeast strains to assess the function of the student-generated mutant alleles: a yckts (yck1::ura3 yck2–2ts) yeast strain in which YCK1 is deleted and the yck2-2ts gene product functions at 24°C but has little activity at 37°C (Robinson et al., 1993), and a yck
strain (yck1::KanMX, yck2::NatMX) in which both YCK1 and YCK2 have been deleted and Yck activity is provided by a plasmid-borne YCK2 allele (pRS316: YCK2; URA3). These tools, available on request, allowed easy manipulation of the YCK2 gene as well as two simple functionality assays. All other molecular biology supplies we used are commercially available, and all bioinformatics tools we used are freely available on the World Wide Web.
Course Context
This project was implemented in Biology 313 (BIOL 313, Genetics) at Centenary College of Louisiana. BIOL 313 is a survey genetics course that is required for all biology majors and is taken by most biochemistry and biophysics majors. The course enrolls between 40 and 50 students each spring, and consists of 3 h of lecture and 3 h of lab each week for 14 wk. There are typically three lab sections, limited to a maximum of 18 students per section. Approximately one-third of the students taking the course are sophomores, approximately 40% are juniors, and approximately one-fourth are seniors. All students taking the course have completed two semesters of general chemistry and a one-semester introductory cell biology course; many are concurrently enrolled in the second semester of organic chemistry. Because the lecture section of the course covers a broad range of topics, ranging from classical genetics to molecular genetics, the lab project proceeds independently of the lecture section of the course. The instructors refer to the lab project whenever relevant topics (e.g., cloning) are covered in lecture, providing students with concrete examples illustrating various lecture topics.
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METHODS |
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Identifying Conserved Sequences in CK1 Enzymes
The instructor reviewed conserved features of protein kinases with each lab section based on three reviews, all of which were made available for students' reference (Hanks et al., 1988; Hanks and Hunter, 1995; Hanks, 2003). After reviewing the concepts of conserved sequences and protein families, students identified conserved amino acid sequences in CK1 enzymes of at least six amino acids. Specifically, students obtained sequences of CK1 enzymes from the National Center for Biotechnology Information (NCBI) protein database (www.ncbi.nlm.nih.gov/sites/entrez), choosing at least one 
, one β, and one 
CK1 as well as the yeast enzymes Yck1 and Yck2. Students aligned these protein sequences using ClustalW (align.genome.jp; Higgins and Sharp, 1988) and identified conserved sequences. The students consulted a table displaying conserved kinase sequences to determine whether these conserved sequences were specific to CK1 enzymes (Hanks and Hunter, 1988).
To put the CK1-specific conserved sequences in context of CK1 structure, the students used Cn3D and the NCBI Structure database to highlight the conserved sequences in a model CK1 (CK1 from Schizosaccharomyces pombe complexed with Mg2+-ATP; www.ncbi.nlm.nih.gov/structure). After identifying the ATP-binding lobe, the substrate-binding lobe, and each of the conserved sequences, the students formed hypotheses about the function of each conserved sequence. Each lab section then chose a single conserved sequence on which to focus, and each lab group (composed of two to three students) determined the mutation within that sequence that they wished to make. The instructor encouraged the lab groups to work together in designing these mutations, suggesting that the mutations could be more informative if different groups made complementary mutations. For example, within a lab section focusing in part on a highly conserved proline, one lab group deleted the proline, one made a conservative mutation, and one made a nonconservative mutation.
Designing Primers
Students obtained the YCK2 open reading frame (ORF) sequence from the Saccharomyces Genome Database (www.yeastgenome.org) and used this to identify the nucleotides corresponding to their conserved amino acid sequence. Using rules for primer design provided with the Stratagene QuikChange kit, students then designed primers to introduce their mutation. Specifically, students attempted to design primers that were between 25 and 45 nucleotides, with a melting temperature of 
78°C, a minimum GC content of 40%, and terminated in one or more C or G bases. The instructor examined each pair of primers and suggested changes when appropriate. When it was not possible to design primers that adhered to all the desired parameters, the instructor often designed a second primer set to increase the probability of a successful mutagenesis reaction. All primers were synthesized by Integrated DNA Technologies (Coralville, IA) at the 100-nmol level and were used without purification.
Site-directed Mutagenesis Mutagenesis reactions were performed using the QuikChange kit according to manufacturer's instructions (Stratagene, Cedar Creek, TX). Unless otherwise noted, all reagents were provided with the QuikChange kit. Briefly, each student group performed two mutagenesis reactions, using 5 and 10 ng of pLR10 (pUC18:GFP-YCK2; Robinson et al., 1999) as template. The GFP fusion in this plasmid has native YCK2 flanking sequences upstream and downstream, including the native YCK2 promoter (Robinson et al., 1999). The forward and reverse primers (125 ng) designed by the students were used in the reactions; when the instructors identified potential shortcomings of the students' primer design, students performed duplicate reactions with a primer set designed by the instructors. The reactions also contained reaction buffer, dNTP mix, PfuTurbo DNA polymerase, and water to a final volume of 50 µl. Reactions were carried out in an Eppendorf thermal cycler as follows: 1 cycle: 95°C 30 s; 18 cycles: 95°C 30 s, 55°C 1 min, 68°C 5 min. Template DNA was then digested by incubation with DpnI for 1 h at 37°C. XL-1 Blue supercompetent cells were thawed on ice and separated into 50-µl aliquots in prechilled 14-ml BD Falcon polypropylene round-bottomed tubes (Thermo Fisher Scientific, Waltham, MA). Supercompetent cells were incubated with 1 µl of each DpnI-treated mutagenesis reaction for 30 min. The cells were heat-shocked at 42°C for 45 s and then incubated on ice for 2 min. Preheated SOC broth was added and cells were incubated for 1 h at 37°C with shaking. Half the volume of each transformation reaction was then plated on Luria-Bertani (LB)-ampicillin medium and incubated at 37°C overnight. Each student group picked three colonies with sterile toothpicks and grew these in LB containing 100 µg/ml ampicillin overnight at 37°C with shaking.
Plasmid Preparation Plasmid minipreps were performed using the Zyppy Prep I miniprep kit (Zymo Research, Orange, CA) according to manufacturer's instructions. Briefly, cells from 3 ml of liquid culture were pelleted by brief centrifugation in a 1.5-ml microfuge tube at full speed. The supernatant was discarded, and the cell pellet was resuspended in buffer P1 and lysed by addition of buffer P2. Buffer P3 was added to precipitate cell debris. The tube was centrifuged for 3 min at full speed, and the supernatant was loaded into the Zymo-spin column, avoiding carrying over any cell debris. The Zymo-spin column and collection tube were centrifuged at full speed for 30 s, allowing the liquid to flow through the column. The flow through in the collection tube was discarded and the resin was washed with wash buffer. The column was transferred to a sterile 1.5-ml microfuge tube and DNA was eluted with 40 µl of water.
Analytical Digest of Mutagenized DNA before Sequencing Miniprep DNA was analyzed by restriction enzyme digest and gel electrophoresis. One microliter of each sample was incubated with 2 U of BamHI and 2 U of SalI in buffer D (all from Promega, Madison, WI) for 1 h at 37°C. The digested samples were then combined with loading buffer (Sambrook et al., 1989), loaded in a 1% agarose gel containing 1 µg/ml ethidium bromide, and subjected to electrophoresis for approximately 1 h at 120 V. Results were visualized with UV light.
Sequencing Each student group chose three samples for sequence analysis. Approximately 1000 ng of DNA to be sequenced and approximately 100 pmol of the appropriate sequencing primer were sent to Retrogen (San Diego, CA) for automated dideoxy sequencing. Due to the high fidelity of PfuTurbo and the cost of multiple sequencing reactions for each clone, only the region of interest was sequenced for each clone for the lab course. Mutations in the LLGPSLED region used the sequencing primer 5'-GGGCTGCACTATAAGATAG-3', mutations in the HIPYRE region were analyzed with the sequencing primer 5'-CTGTTGTACAAGTCG-3', and mutations in the EQSRRDD region were analyzed with the sequencing primer 5'-GGAAGACCGGGTCAACC-3' (all from Integrated DNA Technologies). Students analyzed the results of the sequencing using the BLAST algorithm (Altschul et al., 1990). Specifically, they used BLAST to align the sequences obtained from Retrogen with YCK2 sequence. The alignment was used to verify that their mutant allele was identical to wild-type YCK2 except at the mutation site.
Preparative Digest to Isolate GFP-mYCK2 Fragment Each student group chose one clone containing the desired mutation for further use and subjected it to a preparative digest to remove the GFP-mYCK2 fragment from the vector. Specifically, 2–3 µg of DNA was incubated for 2 h at 37°C in buffer H with 5 U each XbaI and SacI (all from Promega) in a final volume of 25 µl. Samples were then mixed with loading buffer, loaded in a 1% agarose gel containing 1 µg/ml ethidium bromide, and electrophoresed as described above. Results were visualized with UV light, and the band corresponding to the GFP-mYCK2 fragment was excised with a scalpel and stored at 4°C for purification.
GFP-mYCK2 Fragment Purification Purification of the GFP-mYCK2 fragments was performed using a Wizard SV DNA purification kit (Promega, Madison, WI) according to manufacturer's instructions. Briefly, the agarose gel slice was melted in membrane binding solution (MBS), by using 10 µl of MBS for every 10 mg of agarose, at 60°C. The dissolved gel was loaded into an SV minicolumn and incubated for 1 min at room temperature. After the incubation, the minicolumn was centrifuged for 1 min at full speed. The liquid in the collection tube was discarded, and the column was washed twice with membrane wash solution. The SV minicolumn was transferred to a clean 1.5-ml microfuge tube, and 50 µl of water was added. The minicolumn was incubated at room temperature for 1 min and then centrifuged at full speed for 2 min to elute the purified GFP-mYCK2 fragment.
Ligation
To construct low copy plasmid containing GFP-mYCK2 under the control of the native YCK2 promoter, the purified GFP-mYCK2 fragment was ligated into pRS315 (CEN, LEU2; Sikorski and Hieter, 1989). Ligation was performed using a LigaFast kit (Promega) according to manufacturer's instructions. Students incubated 100 ng of GFP-mYCK2 with 70 ng of XbaI/SacI-digested pRS315 shuttle vector in a 16-µl reaction with 3 U of DNA ligase. Reactions were incubated for 10 min at room temperature and then used to transform 100 µl of chemically competent DH5 Escherichia coli cells. Frozen competent cells were thawed on ice, and 100 µl was incubated with the ligation mixture on ice for 30 min. The cells were heat-shocked at 42°C for 3 min and then incubated on ice for 2 min. The cells were then incubated with 0.5 ml of preheated LB for 1 h at 37°C with shaking. Next, 250 µl of each reaction was plated on LB-ampicillin plates and incubated at 37°C overnight. After development of colonies, colonies were inoculated into LB plus 0.1% ampicillin and incubated overnight at 37°C with shaking. Each student group grew four liquid cultures and purified plasmid DNA from each using the miniprep procedure described above.
Analytical Digest of Shuttle Vector: GFP-mYCK2 Construct Miniprep results were analyzed by restriction digest and gel electrophoresis. One microliter of each sample was incubated in a total volume of 10 µl with 2 U of XbaI and 2 U of SacI in buffer H (all from Promega) for 1 h at 37°C. Reactions were then combined with loading buffer and electrophoresed as described above. Results were visualized with UV light.
Preparation of Calf Thymus Carrier DNA Calf thymus DNA (Sigma-Aldrich, St. Louis, MO) was prepared as a 10 mg/ml solution in TE and sheared sequentially with 18-, 22-, and 26-gauge needles. The solution was then autoclaved for 15 min before incubating on ice for 10 min. Aliquots were stored at –20°C. Each aliquot was boiled for 10 min and then placed on ice immediately before use.
Preparation of Yeast Media and Plates Media were prepared as described previously (Sherman et al., 1986).
Yeast Transformation and Culture
Students used a modified version of the LiOAc transformation procedure of Gietz and Schiestl (1991). For each pair of student groups, 10 ml YPD cultures were inoculated with yckts yeast (yck1-1::ura3 yck2-2ts; Robinson et al., 1999) and yck yeast and grown overnight at 24°C with shaking. Approximately 3 h before use, each culture was diluted to 100 ml in YPD and grown at 24°C with shaking. Cells were then pelleted by low-speed centrifugation and the cell pellet was washed with sterile water and resuspended in lithium acetate in TE (0.1 M LiOAc/TE). One hundred microliter aliquots of the competent cells were added to prechilled microfuge tubes containing 75 µg of calf thymus DNA and 2 µg of pRS315:GFP-mYCK2. Each student group carried out a no DNA control (no plasmid), a positive control (2 µg pRS315:GFP-YCK2), and a negative control (2 µg pRS315). Then, 600 µl of 40% polyethylene glycol /0.1 M lithium acetate in TE was added, followed by gentle mixing by inversion. The tubes were then incubated at room temperature for 30 min on a rotating platform. Dimethylsulfoxide (70 µl) was then added to each sample, and each sample was mixed by inversion and then heat shocked at 42°C for 6 min. After rapid cooling for 2 min on ice, cells were pelleted at 3000 rpm for 3 min, the supernatant was discarded, and the pellet was resuspended in 1 ml of –Leu medium. One tenth of each sample was then plated on a –Leu plate by using sterile 4-mm glass beads. The plates were allowed to develop colonies for several days at room temperature (yckts cells) or 30°C (yck cells). Four colonies from each reaction were patched to –Leu plates and grown overnight at 24°C (yckts cells) or at 30°C (yck cells). Patches were then replica plated to two –Leu plates incubated at 24 and 37°C (yckts cells) or to –Leu and 5-fluoro-orotic acid (5-FOA) plates incubated at 30°C (yck cells). Function was assessed by comparing growth in permissive and restrictive conditions.
Visualization
Yeast cells grown overnight on agar medium in restrictive conditions were scraped from patches, suspended in 2–5 µl of water, placed under a coverslip, and examined by bright field and fluorescence microscopy.
Assessment
To determine whether educational goals 1 and 2 were achieved, student knowledge and skills were assessed with a pretest the first day that the lab met. The same test also was included on the final exam as a posttest. To compare responses to individual questions, student responses from each lab section were averaged. A two-tailed paired t test was performed to determine whether the learning gain for each question was significant. To compare individual student learning on the entire test, a two-tailed paired t test was performed without regard to individual lab sections. The test is provided in Supplemental Material 2.
To determine whether educational goal 3 was achieved, student lab reports were assessed using a rubric (provided in Supplemental Material 2). Students wrote a lab report at midterm detailing their results for the first half of the project. They were then allowed to revise this lab report to replace their initial grade. Students also wrote a final lab report detailing the results for the second half of the project, but they were unable to revise this report. Scores on the first lab report were compared with the revision and to the second lab report; in both cases, the significance of the change was determined with a two-tailed paired t test.
Students also completed an attitudes survey at the end of the course assessing their perceptions of the extent to which the lab activities facilitated their learning.
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RESULTS |
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yeast, to perform two independent assays of their mutant allele's function. In the yckts yeast, YCK1 has been deleted and the protein product of yck2-2ts functions at 24°C but has little activity at 37°C (Robinson et al., 1993), allowing the strain to grow at 24°C but not at 37°C. Thus, expression of the mutant alleles in this strain allows the students to perform a complementation test by testing whether their mutant allele sustains growth at 37°C. In the yck strain, both YCK1 and YCK2 have been deleted, and Yck activity is provided by a plasmid-borne YCK2 allele (pRS316: YCK2; URA3). Thus, expression of the mutant alleles in this strain allows the students to perform a plasmid shuffle assay (Elledge and Davis, 1988) to determine whether their mutant gene product can sustain growth in the absence of any other Yck activity. This assay tests whether a resident plasmid that is required for viability can be replaced by an introduced plasmid, taking advantage of the ability to select against cells carrying an intact URA3 gene using 5-FOA. 5-FOA is converted to the toxic compound 5-fluorouracil in the presence of a functional URA3 gene. Because cells cannot grow on 5-FOA medium if they carry the URA3 plasmid, and they cannot grow in the absence of functional Yck, students were able to observe growth of the yck yeast on 5-FOA only if their mutant allele, present on the LEU2 plasmid, encodes a functional Yck2 protein. Growth rate and morphology of the strains on 5-FOA medium can provide indicators of the level of activity of the mutant protein, because each is compromised if activity is low.
For both strains of yeast, the students performed three transformation controls: one control in which cells were incubated only with carrier DNA, to demonstrate that no Leu+ colony could arise in the absence of LEU2 plasmid; a positive control, in which cells were transformed with a plasmid carrying a wild-type GFP-tagged YCK2 gene; and a negative control, in which cells were transformed with the empty LEU2 vector. In each case, the transformed cells were initially grown under conditions that selected for the transforming plasmid (–Leu medium) but were otherwise permissive (i.e., yckts yeast were grown at 24°C; yck yeast were grown in the absence of 5-FOA). After the development of colonies, colonies were patched to fresh media and allowed to develop under the same conditions. Patches were then replica-plated to media incubated in both permissive and restrictive conditions, allowing students to determine the function of their mutant alleles. Representative student results are shown in Figure 3A. A summary of the outcomes of all the student mutations is shown in Table 3.
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Student Learning Outcomes
Student learning was assessed with a knowledge survey at the beginning of the course and after completion of the course. Specifically, this survey was designed to determine whether students gained an understanding of the genetics concepts and molecular biology techniques used within the project. We also included questions to determine whether students had gained the ability to use the bioinformatics tools used during the project. A comparison of the pre- and posttest results displays significant learning gains for all tested areas except one area. Students displayed a significant increase in their understanding of all the molecular techniques used except for DNA sequencing (Figure 4A); the students' ability to answer this question was very high on the pretest, probably due to basic understanding of DNA structure. Students also showed a significant increase in the ability to interpret and predict results from techniques used in the project (Figure 4B), and they showed a significant increase in their ability to use several of the bioinformatics tools used during the project (Figure 4C). In addition to comparing pre- and posttest results for individual questions, we also compared composite pre- and posttest scores for individual students (Figure 4D). This analysis also revealed significant increases in student knowledge, with every student increasing his or her score from the pretest to the posttest.
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DISCUSSION |
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Assessment of student learning indicated that students completing the course showed significant gains in their understanding of the genetics concepts and molecular biology techniques used during the project. They also demonstrated significant gains in their ability to use the bioinformatics tools used in their research and showed an increased ability to communicate the results of their research in the form of a lab report. In assessing the course, we noted several changes we would like to make. Although the pre- and posttest the students completed indicated a significant increase in knowledge in almost all categories, discussions with students completing the course have suggested that it would be helpful to offer the option "I don't know" or "I have no idea" in the future. Not only would this serve to reduce false positives on the pretest (Hood-DeGrenier, 2008), but several students indicated that they would have been more comfortable providing this more honest answer on the pretest. In addition, we would like to include more opportunities for improving scientific presentation skills in the future. To aid in this goal, we plan to add a weekly homework assignment in which students complete a figure, figure legend, and accompanying text for work they completed in lab that week. Not only would this practice allow students to receive feedback on their writing each week but also it would help students construct parts of their lab reports as they progress through the project. Because many students found the lab reports daunting, we feel this progressive construction of materials for the lab report would be helpful. Although the students were somewhat intimidated by the lab reports, the increased scores between lab report 1 and lab report 2 indicate progress not only in learning concepts and techniques but also in ability to understand and interpret results. The difference in weight given to the discussion between lab reports 1 and 2 makes more significant the increased scores, because the discussion was worth a greater fraction of the total points (16 vs. 30%) in lab report 2.
The course enrolls approximately 40–50 students of varied backgrounds every spring. The students enrolled are approximately equally distributed among their sophomore, junior, and senior years, and they are typically biology, biochemistry, biophysics, chemistry, or neuroscience majors. There is one faculty instructor for each section of 15–18 students. The course meets for 3 h/wk for 14 wk, 10 of which are devoted to the project; students are also occasionally required to come in outside of scheduled lab time to complete small tasks to keep the project progressing. With the exception of the two yeast strains described above and the template DNA used in the mutagenesis reaction, all of the tools used in the project are commercially available or freely available on the World Wide Web. The template plasmid used in site-directed mutagenesis and both yeast strains are available upon request from the authors. As described here, the cost of the project is approximately $100/student; the cost could be reduced by decreasing the use of kits, decreasing the number of primers ordered, or decreasing the number of sequencing reactions. It is important to note that all bioinformatics tools used are freely available on the World Wide Web and that all are student-friendly and easy to use.
The project can be modified easily to allow students to investigate any gene for which there is a relatively simple functionality assay. It also can be modified to be a shorter project if site-directed mutagenesis is performed on template DNA that allows direct expression in the model organism, allowing the cloning steps performed in this project to be eliminated. These modifications would be most effectively accomplished in collaboration with an active yeast research lab, but they also could build from collections of yeast deletion strains (Saccharomyces Genome Deletion Project; sequence-www.stanford.edu/group/yeast_deletion_project/deletions3) and overlapping plasmids that cover the yeast genome (steelhead.aecom.yu.edu/SystematicLibrary; www.openbiosystems.com/GeneExpression/Yeast/GenomicTiling).
Finally, the project has proved to be a sound starting point for independent student research projects. Three productive student research projects developed from the initial semester in which this project was implemented. The three students integrated the mutant alleles into the yeast chromosome to better assess the ability of each mutant protein to fulfill requirement for Yck1,2 activity. Students also transferred their mutant alleles into vectors for fusion protein production and isolated and purified fusion protein for in vitro protein kinase assays. These ongoing projects have produced interesting results that the students have presented at a Centenary College research forum. In addition, they will lead to two student presentations at regional or national meetings and likely will be included in one or more research publications.
In summary, the project described here adds to the growing repertoire of inquiry-based projects students may complete in a laboratory course (e.g., Gammie and Erdeniz, 2004; Goyette and DeLuca, 2007). Students use a variety of bioinformatics tools to frame a question and then use common molecular biology techniques to perform their experiment. The project is appropriate for students with a variety of backgrounds, and is flexible enough to allow modification for labs with different time and budget constraints. Finally, the original research aspect of the project adds motivation to complete each step, and it is likely to generate results that can serve as the basis for individual student projects in the instructor's lab, or even to serve as preliminary data for a larger project involving more students. The positive student response to the project indicates that the approach was effective for both motivation and learning.
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ACKNOWLEDGMENTS |
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FOOTNOTES |
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