Structural characterization of a novel KH-domain containing plant chloroplast endonuclease

Chlamydomonas reinhardtii is a single celled alga that undergoes apoptosis in response to UV-C irradiation. UVI31+, a novel UV-inducible DNA endonuclease in C. reinhardtii, which normally localizes near cell wall and pyrenoid regions, gets redistributed into punctate foci within the whole chloroplast, away from the pyrenoid, upon UV-stress. Solution NMR structure of the first putative UV inducible endonuclease UVI31+ revealed an alpha(1)-beta(1)-beta(2)-alpha(2)-alpha(3)-beta(3) fold similar to BolA and type II KH-domain ubiquitous protein families. Three alpha-helices of UVI31+ constitute one side of the protein surface, which are packed to the other side, made of three-stranded beta-sheet, with intervening hydrophobic residues. A twenty-three residues long polypeptide stretch (D54-H76) connecting beta(1) and beta(2) strands is found to be highly flexible. Interestingly, UVI31+ recognizes the DNA primarily through its beta-sheet. We propose that the catalytic triad residues involving Ser114, His95 and Thr116 facilitate DNA endonuclease activity of UVI31+. Further, decreased endonuclease activity of the S114A mutant is consistent with the direct participation of Ser114 in the catalysis. This study provides the first structural description of a plant chloroplast endonuclease that is regulated by UV-stress response

Chickpea

The narrow genetic base of cultivated chickpea warrants systematic collection, documentation and evaluation of chickpea germplasm and particularly wild Cicer species for effective and efficient use in chickpea breeding programmes. Limiting factors to crop production, possible solutions and ways to overcome them, importance of wild relatives and barriers to alien gene introgression and strategies to overcome them and traits for base broadening have been discussed. It has been clearly demonstrated that resistance to major biotic and abiotic stresses can be successfully introgressed from the primary gene pool comprising progenitor species. However, many desirable traits including high degree of resistance to multiple stresses that are present in the species belonging to secondary and tertiary gene pools can also be introgressed by using special techniques to overcome pre- and post-fertilization barriers. Besides resistance to various biotic and abiotic stresses, the yield QTLs have also been introgressed from wild Cicer species to cultivated varieties. Status and importance of molecular markers, genome mapping and genomic tools for chickpea improvement are elaborated. Because of major genes for various biotic and abiotic stresses, the transfer of agronomically important traits into elite cultivars has been made easy and practical through marker-assisted selection and marker-assisted backcross. The usefulness of molecular markers such as SSR and SNP for the construction of high-density genetic maps of chickpea and for the identification of genes/QTLs for stress resistance, quality and yield contributing traits has also been discussed

wss04.pdf

Abstrac

Small cell lung cancer presenting as Cushing's syndrome

A rare case of small cell carcinoma of the lung who presented with Cushing's syndrome and superior vena cava syndrome is described. The relevant literature is reviewed

Bilateral neuro-retinitis following chick embryo cell anti-rabies vaccination – a case report

<p>Abstract</p> <p>Background</p> <p>The Optic nerve is rarely involved after sheep brain anti-rabies vaccination in the form of retrobulbar neuritis or papillitis. Bilateral neuroretinitis after chick embryo cell antirabies vaccination has not been reported.</p> <p>Case presentation</p> <p>We report the case of a 56 year old male who developed bilateral neuro-retinitis following three injections of antirabies vaccine prepared from the chick embryo.</p> <p>Conclusion</p> <p>The chick embryo cell antirabies vaccine can cause bilateral neuroretinits which has not been reported previously.</p