Swati Varshney

Bio: Swati Varshney is an academic researcher from Institute of Genomics and Integrative Biology. The author has contributed to research in topics: Proteome & Proteomics. The author has an hindex of 6, co-authored 27 publications receiving 146 citations. Previous affiliations of Swati Varshney include Indian Institute of Technology Delhi & University of Melbourne.

Micro RNAs upregulated in Vitiligo skin play an important role in its aetiopathogenesis by altering TRP1 expression and keratinocyte-melanocytes cross-talk.

Abstract: Translation of genes is regulated by many factors including microRNAs (miRNAs). miRNA profiling of lesional and non-lesional epidermal RNA from 18 vitiligo patients revealed significant upregulation of 29 miRNAs in the lesional epidermis, of which 6 miRNAs were transfected in normal human epidermal keratinocytes (NHEKs) to study their downstream effects using quantitative proteomics. Many proteins involved in oxidative stress, Vesicle trafficking, Cellular apoptosis, Mitochondrial proteins and Keratins were regulated after miRNA transfections in the keratinocytes. However, tyrosinase related protein-1 (TRP1/TYRP1), a melanogenesis protein, was consistently downregulated in NHEKs by all the six miRNAs tested, which was quite intriguing. TRP1 was also downregulated in lesional epidermis compared with non-lesional epidermis. Since melanocytes synthesize and transfer melanosomes to the surrounding keratinocytes, we hypothesized that downregulation of TRP1 in NHEKs may have a role in melanosome transfer, which was confirmed by our co-culture experiments. Downregulation of TRP1 in keratinocytes negatively affected the melanosome transfer from melanocytes to keratinocytes resulting in melanin accumulation which may be leading to melanin induced cytotoxicity in melanocytes. Regulation of key processes involved in aetiopathogenesis of vitiligo along with TRP1 suggests that miRNAs act in an integrated manner which may be detrimental for the loss of melanocytes in vitiligo.

Galectin-7 Impairs Placentation and Causes Preeclampsia Features in Mice.

Abstract: Preeclampsia is a serious pregnancy-induced disorder unique to humans. The etiology of preeclampsia is poorly understood; however, poor placental formation is thought causal. Galectin-7 is produced by trophoblast and is elevated in first-trimester serum of women who subsequently develop preeclampsia. We hypothesized that elevated placental galectin-7 may be causative of preeclampsia. Here, we demonstrated increased galectin-7 production in chorionic villous samples from women who subsequently develop preterm preeclampsia compared with uncomplicated pregnancies. In vitro, galectin-7 impaired human first-trimester trophoblast outgrowth, increased placental production of the antiangiogenic sFlt-1 splice variant, sFlt-1-e15a, and reduced placental production and secretion of ADAM12 (a disintegrin and metalloproteinase12) and angiotensinogen. In vivo, galectin-7 administration (E8-E12) to pregnant mice caused elevated systolic blood pressure, albuminuria, impaired placentation (reduced labyrinth vascular branching, impaired decidual spiral artery remodeling, and a proinflammatory placental state demonstrated by elevated IL1β, IL6 and reduced IL10), and dysregulated expression of renin-angiotensin system components in the placenta, decidua, and kidney, including angiotensinogen, prorenin, and the angiotensin II type 1 receptor. Collectively, this study demonstrates that elevated galectin-7 during placental formation contributes to abnormal placentation and suggests that it leads to the development of preeclampsia via altering placental production of sFlt-1 and renin-angiotensin system components. Targeting galectin-7 may be a new treatment option for preeclampsia.

MicroRNAs: Target Recognition and Regulatory Functions

Abstract: MicroRNAs (miRNAs) are endogenous ∼23 nt RNAs that play important gene-regulatory roles in animals and plants by pairing to the mRNAs of protein-coding genes to direct their posttranscriptional repression. This review outlines the current understanding of miRNA target recognition in animals and discusses the widespread impact of miRNAs on both the expression and evolution of protein-coding genes.

Quantification of biofilm in microtiter plates: overview oftesting conditions and practical recommendations for assessmentof biofilm production by staphylococci.

Abstract: The details of all steps involved in the quantification of biofilm formation in microtiter plates are described. The presented protocol incorporates information on assessment of biofilm production by staphylococci, gained both by direct experience as well as by analysis of methods for assaying biofilm production. The obtained results should simplify quantification of biofilm formation in microtiter plates, and make it more reliable and comparable among different laboratories.

Metabolomics: A Way Forward for Crop Improvement.

Abstract: Metabolomics is an emerging branch of “omics” and it involves identification and quantification of metabolites and chemical footprints of cellular regulatory processes in different biological species. The metabolome is the total metabolite pool in an organism, which can be measured to characterize genetic or environmental variations. Metabolomics plays a significant role in exploring environment–gene interactions, mutant characterization, phenotyping, identification of biomarkers, and drug discovery. Metabolomics is a promising approach to decipher various metabolic networks that are linked with biotic and abiotic stress tolerance in plants. In this context, metabolomics-assisted breeding enables efficient screening for yield and stress tolerance of crops at the metabolic level. Advanced metabolomics analytical tools, like non-destructive nuclear magnetic resonance spectroscopy (NMR), liquid chromatography mass-spectroscopy (LC-MS), gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography (HPLC), and direct flow injection (DFI) mass spectrometry, have sped up metabolic profiling. Presently, integrating metabolomics with post-genomics tools has enabled efficient dissection of genetic and phenotypic association in crop plants. This review provides insight into the state-of-the-art plant metabolomics tools for crop improvement. Here, we describe the workflow of plant metabolomics research focusing on the elucidation of biotic and abiotic stress tolerance mechanisms in plants. Furthermore, the potential of metabolomics-assisted breeding for crop improvement and its future applications in speed breeding are also discussed. Mention has also been made of possible bottlenecks and future prospects of plant metabolomics.

Identification of differentially expressed proteins in fresh and frozen-thawed boar spermatozoa by iTRAQ-coupled 2D LC-MS/MS.

Abstract: Cryodamage is a major problem in semen cryopreservation, causing changes in the levels of proteins that influence the function and motility of spermatozoa In this study, protein samples prepared from fresh and frozen-thawed boar spermatozoa were compared using the isobaric tags for relative and absolute quantification (iTRAQ) labeling technique coupled to 2D LC-MS/MS analysis A total of 41 differentially expressed proteins were identified and quantified, including 35 proteins that were present at higher levels and six proteins that were present at lower levels in frozen-thawed spermatozoa by at least a mean of 179-fold (P<005) On classifying into ten distinct categories using bioinformatic analysis, most of the 41 differentially expressed proteins were found to be closely relevant to sperm premature capacitation, adhesions, energy supply, and sperm-oocyte binding and fusion The expression of four of these proteins, SOD1, TPI1, ODF2, and AKAP3, was verified by western blot analysis We propose that alterations in these identified proteins affect the quality of cryopreserved semen and ultimately lower its fertilizing capacity This is the first study to compare protein levels in fresh and frozen-thawed spermatozoa using the iTRAQ technology Our preliminary results provide an overview of the molecular mechanisms of cryodamage in frozen-thawed spermatozoa and theoretical guidance to improve the cryopreservation of boar semen