Isolation of RNA and RT-PCR, cloning, and sequencing of noncoding RNAs from fungi*

A critical analysis of assessment quality in genomics and bioinformatics education research

The growing importance of genomics and bioinformatics methods and paradigms in biology has been accompanied by an explosion of new curricula and pedagogies. An important question to ask about these educational innovations is whether they are having a meaningful impact on students' knowledge, attitudes, or skills. Although assessments are necessary tools for answering this question, their outputs are dependent on their quality. Our study 1) reviews the central importance of reliability and construct validity evidence in the development and evaluation of science assessments and 2) examines the extent to which published assessments in genomics and bioinformatics education (GBE) have been developed using such evidence. We identified 95 GBE articles (out of 226) that contained claims of knowledge increases, affective changes, or skill acquisition. We found that 1) the purpose of most of these studies was to assess summative learning gains associated with curricular change at the undergraduate level, and 2) a minority (<10%) of studies provided any reliability or validity evidence, and only one study out of the 95 sampled mentioned both validity and reliability. Our findings raise concerns about the quality of evidence derived from these instruments. We end with recommendations for improving assessment quality in GBE.

PCR cloning of partial nbs sequences from grape (Vitis aestivalis Michx)

Plants defend themselves against pathogens via the expressions of disease resistance (R) genes. Many plant R gene products contain the characteristic nucleotide-binding site (NBS) and leucine-rich repeat (LRR) domains. There are highly conserved motifs within the NBS domain which could be targeted for polymerase chain reaction (PCR) cloning of R genes. Here, we report a 4-week undergraduate laboratory exercise that mimics the research environment to PCR-clone partial nbs sequences using degenerate primers corresponding to the phosphate-binding loop (P-loop) and GLPL motifs within the NBS domain of potential R gene products from the North American grape, Vitis aestivalis Michx. Students were able to complete the laboratory procedures successfully and obtained four different clones, among which three are new. Through the laboratory exercise, students learned a variety of important molecular techniques including genomic DNA isolation, DNA quantification, PCR, agarose gel electrophoresis, DNA extraction from agarose gel, ligation, bacterial transformation, and plasmid DNA isolation and purification. They also used currently available web-based bioinformatic programs for sequence analysis. The laboratory exercise provides students the hands-on experience on PCR cloning and shows them how it is done in a research environment. The clones obtained may be further tested for their potential use as markers to differentiate resistant cultivars from the susceptible ones, a useful tool in breeding programs.