Endocrinology & Metabolic Syndrome
Open Access
ISSN: 2161-1017
+44 1478 350008
ISSN: 2161-1017
+44 1478 350008
Dheer Singh
Accepted Abstracts: Endocrinol Metab Synd
A key to efficient female reproduction performance is the proper function of the ovarian cycle that is characterized by growth, selection, ovulation and luteinization of healthy follicles. All these process but also placentation, pregnancy and parturition are essentially regulated by ovarian hormones, the important being estrogen (E2). The Cyp19 gene encodes the key enzyme of estrogen biosynthesis, aromatase cytochrome P450 (P450arom). In the present study the tissue-specific expression of P450arom, transcript variants and its regulation in different stages of follicular development and differentiation and during pregnancy were analyzed. Nested PCR approach showed that granulosa cells from ovarian large follicles exhibit significant higher expression of aromatase mRNA as compare to that in other tissues. Its expression declined in corpus luteum. To understand its tissue specific regulation, isolation and analysis of tissue-specific transcripts by 5?RACE and RT-PCR showed that the promoter II is the major promoter responsible for aromatase expression in the preovulatory stages and promoter I.1 in postovulatory structure (corpus luteum) and during pregnancy in buffalo. The respective proximal (PII) and distal (PI.1) promoter regions of buffalo Cyp19 gene were cloned using PCR technique. To elucidate if the epigenetic mechanisms as tissueand differentiation-specific DNA methylation involved in the aromatase gene expression, methylation status of individual CpG dinucleotide, within each of the promoter II and I.1, was analyzed with bisulfite direct sequencing in granulosa cells of different sized follicles and placental cotyledons during different sates of pregnancy . The methylation data suggested that methylation of individual CpG, relative to start site of transcription of respective promoters, coincides with its tissue specific transcript expression. Tissue specific transcript expression and it epigenetic regulation could be of importance in tissue -specific regulation of Cyp19 gene in mammals.
Dheer Singh received Ph.D degree from National Dairy Research Institute (NDRI) Deemed University at Karnal (Haryana) in India. After his doctoral degree he selected as Agricultural Research Scientist (ARS) and joined Animal Biochemistry Division at NDRI as scientist and subsequently promoted to Principal Scientist. Awarded BOYSCAST (Better opportunity for young scientist in chosen area of science and technology) fellowship from Department of science and Technology (DST), Ministry of Science and Technology, Govt. of India to pursue higher study abroad and worked in Department of Cell Biology and Developmental and Anatomy at School of Medicine, University of South Carolina, USA in the area of transcriptional regulation of eukaryotic genes. Life member of prominent professional national scientific societies namely, SBC, India, ISSRF, ISCB etc. Elected as national executive member of ISSRF in 2006 & 2008 and since is working as national executive member of ISSRF. Apart from several educational fellowships such as ICMR Junior research fellowship (JRF), NDRI JRF and SRF etc, awarded of 9th & 11Th AAAP/CAPI Outstanding Research Award of of Asian Australian Animal Production Society and prestigious Labhsetwar award -2013 of Indian Society for Study in Reproduction & Fertility. Handled more than 15 research project funded by various funding agencies including an Indo-German joint collaborative project (DST-DFG & DST-DAAD) on epigenetic regulation of genes. Major focus of research of his lab is 1) Identification and analysis of the regulation of selected traitaffecting (e.g. fertility) genes. 2) Application of RNA interference tools for livestock functional genomics, 3) Epigenetic regulation of gene expression.