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MN, S.

Publications and source records attributed to MN, S..

2 recordsLinked to original sources

DNA barcode developement based on chloroplast and ITS genes for species identification of endangered and threated species of Western Ghats, India

Accurate identification is crucial for conserving species, especially in regions such as the Western Ghats, where trade poses a significant threat to endangered and threatened forest species. Traditional morphology-based identification can be challenging and time-consuming, leading to inaccuracies, especially with similar-looking species or dried specimens. Therefore, DNA barcoding offers a potent solution for precise species identification to address illicit trade and address impactful conservation measures. DNA barcoding is a taxonomic technique that uses standardized short DNA sequences to differentiate and classify species. This approach is especially valuable when morphological characteristics alone are insufficient for accurate species identification. In this study, we focused on the development of a DNA barcoding system for the efficient and accurate identification of threatened and endangered important forest species of Western Ghats Karnataka. To develop the DNA barcoding system, a multilocus approach utilizing sixteen standard DNA barcoding markers was used. A total of 47 threatened and endangered forest species from the Western Ghats were selected for this study. Using a larger number of markers to develop DNA barcodes led to the most precise species identification rates. Moreover, the wide availability of DNA barcode databases allows for quick and accurate species identification. In our study, we observed the highest amplification rates for rbcL1 (40 species), psbtrnH2 (36 species), and PsbA-trnH1 (33 species). DNA amplification varied from 11.76% to 94.11%. Notably, the highest DNA amplification rates were detected for A. wightii (94.11%) and A. hondala (92.34%), both of which belong to the Arecaceae and Passifloraceae families, respectively. Sequencing success rates ranged from 37.5% to 100%. This study will aid in the development of a database of available threatened forest species in western Ghats Karnataka and other regions.

plant biology↗

BRCA1 expression, its correlation with clinicopathological features and response to neoadjuvant chemotherapy in high grade serous ovarian cancer from an Indian centre

In high grade serous ovarian cancers (HG-SOC), BRCA1/2 mutations have been reported as the most predominant mutations by various studies. However, the non-mutational mechanisms of BRCA pathway inactivation in HG-SOC are unclear. We aimed to evaluate BRCA1 inactivation by estimating its expression along with its repressor in primary and neoadjuvant chemotherapy (NACT) treated HG-SOC tumors with known therapeutic response. The expression pattern of BRCA1 protein was evaluated by immunohistochemistry (IHC) in 119 cases of HG-SOC from a hospital cohort consisting of primary (N= 69) and NACT treated (N=50) tumors. Histological patterns (SET), stromal infiltration by lymphocytes (sTILs) and chemotherapy response score (CRS) were estimated by microscopic examination. Gene expression levels of BRCA1, and its repressor ID4 was estimated by qPCR. Association of BRCA1 protein and mRNA with clinicopathological features was studied. Relevance of the BRCA1/ID4 ratio was evaluated in tumors with different CRS. BRCA1 protein expression was observed in 12% of primary and 19% of NACT treated HG-SOC tumors. Moderate concordance was observed between BRCA1 protein and mRNA expression (AUC-0.677). High BRCA1 mRNA expression was significantly associated with more frequent SET pattern (p=0.024), higher sTILs density (p=0.042), increased mitosis (p=0.028). BRCA1 negative tumors showed higher expression of ID4 though not statistically significant. Higher BRCA1/ID4 ratio was associated with high sTILs density in primary (p=0.042) and NACT treated tumors (p=0.040). Our findings show the utility of BRCA1/ID4 ratio to predict neoadjuvant therapy response, which needs further evaluation in larger cohort with long term outcomes.

cancer biology↗