DNA methylation affects important developmental processes in both plants and animals. The process of methylation of cytosines at C‐5 is catalysed by DNA methyltransferases (MTases), which are highly conserved, both structurally and functionally, in eukaryotes. In this study, we identified and characterized cytosine DNA MTase genes that are activated with the onset of reproductive development in rice. The rice genome (Oryza sativa L. subsp. japonica) encodes a total of 10 genes that contain the highly conserved MTase catalytic domain. These genes have been categorized into subfamilies on the basis of phylogenetic relationships. A microarray‐based gene expression profile of all 10 MTases during 22 stages/tissues that included 14 stages of reproductive development and five vegetative tissues together with three stresses, cold, salt and dehydration stress, revealed specific windows of MTase activity during panicle and seed development. The expression of six methylases was specifically/preferentially upregulated with the initiation of floral organs. Significantly, one of the MTases was also activated in young seedlings in response to cold and salt stress. The molecular studies presented here suggest a greater role for these proteins and the epigenetic process in affecting genome activity during reproductive development and stress than was previously anticipated.

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Heat shock proteins (HSPs) perform significant roles in conferring abiotic stress tolerance to crop plants. In view of this, HSPs and their encoding genes were extensively characterized in several plant species; however, understanding their structure, organization, evolution and expression profiling in a naturally stress tolerant crop is necessary to delineate their precise roles in stress-responsive molecular machinery. In this context, the present study has been performed in C4 panicoid model, foxtail millet, which resulted in identification of 20, 9, 27, 20 and 37 genes belonging to SiHSP100, SiHSP90, SiHSP70, SiHSP60 and SisHSP families, respectively. Comprehensive in silico characterization of these genes followed by their expression profiling in response to dehydration, heat, salinity and cold stresses in foxtail millet cultivars contrastingly differing in stress tolerance revealed significant upregulation of several genes in tolerant cultivar. SisHSP-27 showed substantial higher expression in response to heat stress in tolerant cultivar, and its over-expression in yeast system conferred tolerance to several abiotic stresses. Methylation analysis of SiHSP genes suggested that, in susceptible cultivar, higher levels of methylation might be the reason for reduced expression of these genes during stress. Altogether, the study provides novel clues on the role of HSPs in conferring stress tolerance.

Context:The gingival biotype is of utmost importance for esthetics and biologic function. Anatomical characteristic of periodontium such as gingival thickness (GT), width of keratinized gingiva, and alveolar bone morphology will determine the behavior of periodontium when subjected to physical, chemical, or bacterial insult or during therapeutic procedure.Aims:The aim of this study was to correlate the GT with gingival width (GW), probing depth (PD), and papillary fill (PF) in relation to maxillary anterior region.Settings and Design:Undergraduate dental students and interns from a dental college in Navi Mumbai were enrolled in the study according to the inclusion criteria. Six teeth per subject were assessed; a total of 2178 maxillary anterior teeth were examined.Subjects and Methods:Subjects were examined clinically for GT, width of keratinized gingiva, pocket depth, and interdental PF. The data obtained was tabulated and subjected to statistical analysis.Statistical Analysis Used:Spearman's correlation analysis test was performed to find the correlation of GT with GW, PD, and PF.Results:Positive correlation was found between GT and GW (r = 0.241). No significant correlation could be found between GT and PD; and between GT and PF.Conclusions:The present study confirmed a positive correlation between GT and GW. A weak negative correlation was found between GT and PD.

A simplified staging for malignant epithelial tumors of the anal canal is presented. The pattern of recurrence in males is pelvic and perineum, in females pelvis and posterior vaginal wall. Concomitant posterior vaginectomy is advocated. The disease is more common in females than males (4:1). There is little difference between histologic types, i.e. cloacagenic or squamous cell type. Recurrence and survival depend upon depth of invasion and extent of spread rather than histologic cell type. The tumors respond to well-designed surgery, radiotherapy and probably chemotherapy.