Preliminary studies on differential defense responses induced during plant communication

We compared the expression patterns of three representative genes in undamaged tomato and tobacco plants in response to exposure to either tomato or tobacco fed on by Helicoverpa armigera (cotton bollworm). When tomato and tobacco, two species of one family, were incubated in the chambers with the tomato plants damaged by the cotton bollworm, the expression of the PR1, BGL2, and PAL genes was up-regulated in leaves of both plants. However, the levels of gene expression were significantly higher in the tomato than that in the tobacco. In addition, the activities of enzymes, peroxidase, polyphenol oxidase, and lipoxygenase were found to be higher in the tomato than those in the tobacco. Similar results were obtained when the damaged plants were replaced by the tobacco.

Protein kinase C/ζ (PRKCZ) Gene is associated with type 2 diabetes in Han population of North China and analysis of its haplotypes

AIM: To identify the susceptible gene (s) for type 2 diabetes in the prevousely mapped region, 1p36.33-p36.23, in Han population of North China using single nucleotide polymorphisms (SNPs) and to analyze the haplotypes of the gene (s) related to type 2 diabetes.METHODS: Twenty three SNPs located in 10 candidate genes in the mapped region were chosen from public SNP domains with bioinformatic methods, and the single base extension (SBE) method was used to genotype the loci for 192 sporadic type 2 diabetes patients and 172 normal individuals, all with Hah ethical origin, to perform this casecontrol study. The haplotypes with significant difference in the gene (s) were further analyzed.RFSULTS: Among the 23 SNPs, 8 were found to be common in Chinese Han population. Allele frequency of one SNP,rs436045 in the protein kinase C/ζgene (PRKCZ) was statistically different between the case and control groups (P＜0.05). Furthermore, haplotypes at five SNP sites of PRKCZ gene were identified.CONCLUSION: PRKCZgene may be associated with type 2 diabetes in Hah population in North China. The haplotypes at five SNP sites in this gene may be responsible for this association.

Characterization of a novel toxin-antitoxin module,VapBC,encoded by Leptospira interrogans chromosome

Comparative genomic analysis of the coding sequences (CDSs) of Leptospira interrogans revealed a pair of closely linked genes homologous to the vapBC loci of many other bacteria with respect to both deduced amino acid sequences and operon organizations. Expression of single vapC gene in Escherichia coli resulted in inhibition of bacterial growth,whereas co-expression of vapBC restored the growth effectively. This phenotype is typical for three other characterized toxin-antitoxin systems of bacteria, i.e., mazEF[1], relBE[2] and chpIK[3]. The VapC proteins of bacteria and a thermophilic archeae, Solfolobus tokodaii, form a structurally distinguished group of toxin different from the other known toxins of bacteria. Phylogenetic analysis of both toxins and antitoxins of all categories indicated that although toxins were evolved from divergent sources and may or may not follow their speciation paths (as indicated by their 16s RNA sequences), co-evolution with their antitoxins was obvious.

Microbial Genomics Research in China

Microorganisms, including phage/virus, were initial targets and tools for developing DNA sequencing technology. Microbial genomic study was started as a model system for the Human Genome Project (HGP) and it did successfully supported the HGP, particularly with respect to BAC contig construction and large-scale shotgun sequencing and assembly. Microbial genomics study has become the fastest developed genomics discipline along with HGP, taking the advantage of the organisms' highly diversified physiology, extremely long history of evolution, close relationship with human/environment,as well as relatively small genome sizes and simple systems for functional analysis.