ARTICLE | doi:10.20944/preprints202202.0357.v1
Subject: Life Sciences, Molecular Biology Keywords: granulosa cells; heat stress; apoptosis; oxidative stress; RNA-seq; transcriptomics; differentially expressed genes; signaling pathways
Online: 28 February 2022 (11:08:42 CET)
Heat stress affects the granulosa cells (GCs) and ovarian follicular microenvironment, causing poor oocyte developmental competence and fertility. This study aimed to investigate the physical responses and global transcriptomic changes in bovine GCs to acute heat stress (43 ℃ for 2 h) in-vitro and gave essential insights into the general interaction at cell–stress nexus. Heat-stressed GCs exhibited transient proliferation senescence, resumed proliferation at 48 h post-stress. While post-stress immediate culture-media change had a relatively positive effect on proliferation resumption. Increased accumulation of reactive oxygen species and apoptosis was observed in heat stress group. In spite of the upregulation of pro-apoptotic and caspase executioner genes, antioxidants and anti-apoptotic genes were also upregulated in heat-stressed GCs. Progesterone and Estrogen hormones along with steroidogenic genes expression, declined significantly, in spite of the upregulation of genes involved in cholesterol synthesis. Out of 12385 differentially expressed genes (DEGs), 330 significant DEGs (75 upregulated, 225 downregulated) were subjected to KEGG functional pathway annotation, gene ontology enrichment, and STRING network analyses. Based on the manual query of DEGs, pathway and enrichment analyses, a vast interplay observed among all major signaling pathways strongly evidence the repression of cellular transcriptional and proliferation activity, averting the effects of heat stress through remodeling of cellular structural proteins and energetic-homeostasis. This study presents detailed responses of acute heat-stressed GCs at physical, transcriptional, and pathway levels and presents interesting insights into future studies regarding GCs adaptation and their interaction with oocyte and reproductive system at ovarian level.
ARTICLE | doi:10.20944/preprints202204.0248.v1
Subject: Life Sciences, Molecular Biology Keywords: granulosa cells; heat stress; integrated analysis; transcriptomics; metabolomics; differentially ex-pressed genes; metabolites; signaling pathways; metabolic pathways; cancer pathways
Online: 27 April 2022 (05:08:15 CEST)
Previous studies reported the physical, transcriptomics and metabolomics changes in in-vitro acute heat stressed bovine granulosa cells. Granulosa cells exhibited transient proliferation senescence, oxidative stress, increased rate of apoptosis, and decline in steroidogenic activity. This study performs joint integration and network analysis of metabolomics and transcriptomics data to further narrow down and elucidate the role of differentially expressed genes, important metab-olites and relevant cellular and metabolic pathways in acute heat-stressed granulosa cells. Among significant (Raw P-value <0.05) metabolic pathways where metabolites and genes did converge, this study found Vitamin B6 metabolism, Glycine, serine and threonine metabolism, Phenylalanine metabo-lism, Arginine biosynthesis, Tryptophan metabolism, Arginine and proline metabolism, Histidine metabolism, and Glyoxylate and dicarboxylate metabolism. Important significant convergent bio-logical pathways included, ABC transporters and Protein digestion and absorption, while func-tional signaling pathways included cAMP, mTOR, and AMPK signaling pathways together with Ovarian steroidogenesis pathway. Among caner pathways, the most important pathway was Central carbon metabolism in cancer. Through multiple analysis query, Progesterone, Serotonin, citric acid, Pyridoxal, L-Lysine, Succinic acid, L-Glutamine, L-Leucine, L-Threonine, L-Tyrosine, Vitamin B6, Choline, and CYP1B1, MAOB, VEGFA, WNT11, AOX1, ADCY2, ICAM1, PYGM, SLC2A4, SLC16A3, HSD11B2 and NOS2 appeared to be important enriched metabolites and genes, respectively. These genes, metabolites, metabolic, cellular and cell signaling pathways com-prehensively elucidate the mechanisms underlying the intricate fight between death and survival in acute heat-stressed bovine granulosa cells, and essentially help further our understanding and future quest of research in this direction.
ARTICLE | doi:10.20944/preprints202211.0380.v1
Subject: Life Sciences, Genetics Keywords: Heat stress response; novel transcripts; RNA-Sequencing; blood; liver; adrenal glands; rats
Online: 21 November 2022 (07:18:32 CET)
The molecular mechanisms underlying heat stress tolerance in animals to high temperatures remain unclear. This experiment was performed with Sprague-Dawley rats housed at 22 ℃ (control group; CT), and 42 ℃ for 30 min (H30), 60 min (H60), and 120 min (H120). Transcriptomic analysis using RNA-Sequencing (RNA-Seq) from blood (CT and H120), liver (CT, H30, H60, and H120), and adrenal glands (CT, H30, H60, and H120) was performed. The differentially expressed mRNA isoforms (DEIs) were identified and annotated by the CLC Genomics Workbench. Biological process and metabolic pathway analyses were performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) database. A total of 225, 5,764, and 4,988 DEIs in the blood, liver, and adrenal glands were observed. Furthermore, the number of novel differentially expressed transcript lengths with annotated genes and the novel differentially expressed transcript with non-annotated genes were 136 and 8 in blood, 3,549 and 120 in the liver, as well as 3,078 and 220 in adrenal glands, respectively. A total of 35 genes were involved in the heat stress response, out of which Dnaja1, LOC680121, Chordc1, AABR07011951.1, Hsp90aa1, Hspa1b, Cdkn1a, Hmox1, Bag3 and Dnaja4 were commonly identified in the liver and adrenal glands, suggesting that these genes may regulate heat stress response through interactions between liver and adrenal glands. The results suggest that the identified mRNA isoforms could be considered as potential candidates for selecting mammals to improve thermotolerance.