抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Many plant-associated microbes are pathogens that impair plant growth and reproduction. Plants respond to infection using a two-branched innate immune system. The first branch recognizes and responds to molecules common to many classes of microbes, including non-pathogens. The second responds to pathogen virulence factors, either directly or through their effects on host targets. These plant immune systems, and the pathogen molecules to which they respond, provide extraordinary insights into molecular recognition, cell biology and evolution across biological kingdoms. A detailed understanding of plant immune function will underpin crop improvement for food, fibre and biofuels production.

http://www.segenetica.es/cng2/cng2008/biblio/Ref-Marc-Valls---Jones-and-Dangl-Nat06.pdf

The plant immune system

J. Appl. Cryst.の発刊に際して

BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

“Bioinformatics” 특집을 내면서

We have produced a draft sequence of the rice genome for the most widely cultivated subspecies in China, Oryza sativa L. ssp. indica, by whole-genome shotgun sequencing. The genome was 466 megabases in size, with an estimated 46,022 to 55,615 genes. Functional coverage in the assembled sequences was 92.0%. About 42.2% of the genome was in exact 20-nucleotide oligomer repeats, and most of the transposons were in the intergenic regions between genes. Although 80.6% of predicted Arabidopsis thaliana genes had a homolog in rice, only 49.4% of predicted rice genes had a homolog in A. thaliana. The large proportion of rice genes with no recognizable homologs is due to a gradient in the GC-content of rice coding sequences.

/pdf/a-draft-sequence-of-the-rice-genome-oryza-sativa-l-ssp-5212kgt1ff.pdf

A draft sequence of the rice genome (Oryza sativa L. ssp indica)

Tyrosine sulfation is a post-translational modification that influences interaction specificity between certain receptors and their protein ligands in diverse biological processes. For example, rice XA21 receptor-mediated recognition of the sulfated bacterial protein RaxX activates an immune response and triggers resistance to the phytopathogen Xanthomonas oryzae pv. oryzae (Xoo). A five kb raxX-raxSTAB gene cluster of Xoo encodes RaxX, the RaxST tyrosylprotein sulfotransferasea and the RaxA and RaxB components of a predicted proteolytic maturation and ATP-dependent peptide secretion complex. The complete raxX-raxSTAB gene cluster was found only in Xanthomonas species, and its distribution is consistent with multiple gain and loss events during Xanthomonas speciation. Homologs of the raxST gene are present in genome sequences of diverse bacterial species. Together, these results establish a foundation for investigating biological roles for tyrosine sulfation in bacteria.

http://www.biorxiv.org/content/early/2017/06/14/149930.full.pdf

Distribution and inheritance of a gene cluster encoding a sulfated tyrosine peptide in Xanthomonas spp.

The rice pathogen recognition receptor, XA21, confers resistance to Xanthomonas oryzae pv. oryzae (Xoo) strains expressing the pathogen-associated molecule, AvrXA21. XA21 codes for a receptor-like kinase consisting of an extracellular leucine rich repeat (LRR) domain, a transmembrane domain, and a cytoplasmic kinase domain (Ronald et al., 1992; Song et al., 1995). We show that AvrXA21 activity requires the presence of rax (required for AvrXA21) A, raxB, and raxC genes that encode components of a type one secretion system (TOSS). In contrast, an hrpC- strain deficient in type three secretion maintains AvrXA21 activity. Xanthomonas campestris pv. campestris (Xcc) can express AvrXA21 activity if raxST, encoding a putative sulfotransferase, and raxA are provided in trans. Expression of rax genes is dependent on population density and other functioning rax genes, suggesting that AvrXA21 is involved in quorum sensing and that the AvrXA21 pathogen-associated molecule represents an entirely new class of Gramnegative bacterial signaling molecules. We discuss the implications of these results for models of plant innate immunity.

Xanthomonas oryzae pv. oryzae AvrXA21 Activity Is Dependent on a Type One Secretion System, Is Regulated by a Two-Component Regulatory System that Responds to Cell Population Density, and Is Conserved in Other Xanthomonas spp.

Front-runners in plant-microbe interactions Editorial overview

Radically rethinking agriculture for the 21st century. Perspective

The invention provides methods of engineering plants to modulate hydroxycinnamic acid content. The invention additionally provides compositions and methods comprising such plants.

Pamela C. Ronald

Papers

Distribution and inheritance of a gene cluster encoding a sulfated tyrosine peptide in Xanthomonas spp.

Xanthomonas oryzae pv. oryzae AvrXA21 Activity Is Dependent on a Type One Secretion System, Is Regulated by a Two-Component Regulatory System that Responds to Cell Population Density, and Is Conserved in Other Xanthomonas spp.

Front-runners in plant-microbe interactions Editorial overview

Radically rethinking agriculture for the 21st century. Perspective

Modulation of expression of acyltransferases to modify hydroxycinnamic acid content