Tao Zhang,Li-hong Ma,Qian-hao Zhu,Xin-yu Zhang,Chu-yi Nie,Jing-ya Zhou,Jie Sun,Feng Liu
Auxin (Indole-3-acetic acid, IAA) is essential for anther development and male fertility, but little is known about its homeostasis in developing anthers due to its complex and diverse synthesis pathways. Here, we employed transcriptomic, targeted metabolomic, and amino acid analyses on a wild type (WT) cotton ( Gossypium hirsutum ) line SD98–6 and its nearly-isogenic male sterile (MS) line SD98–6A, to delve into the relationship between IAA and anther fertility. In WT anthers, IAA homeostasis was achieved mainly through self-synthesis, conjugate hydrolysis, and polar transport, and accumulation of IAA exhibited an inverted "U" pattern with the highest content observed at the tetrad stage. In MS anthers, no IAA accumulation was observed after the meiosis stage and the IAA content remained constantly low, mainly due to reduction of the substrates (phenylalanine and tryptophan) for IAA synthesis, and significantly decreased expression of the genes involved in IAA synthesis. Meanwhile, carbohydrate metabolism pathways directly contributing to IAA synthesis and synthesis of amino acids were malfunctional in MS anthers based on the expression profile of the metabolic genes and content measurement. These results provide valuable insights into the IAA homeostasis in cotton anthers and imply that genes related to IAA homeostasis are potential targets for development of IAA-sensitive male sterile cotton lines.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been spreading globally for over 2 years, causing serious contagious disease and incalculable damage. The introduction of vaccines has slowed the spread of SARS-CoV-2 to some extent, but there remains a need for specific and effective treatment. The high chemical diversity and safety profiles of natural products make them a potential source of effective anti-SARS-CoV-2 drugs. Cotton plant is one of the most important economic and medical crops and is the source of a large number of antiviral phytochemicals. In this work, we used SARS-CoV-2 main protein (M pro ) as the target to identify potential anti-SARS-CoV-2 natural products in cotton. An in vitro assay showed that of all cotton tissues examined, cotton flower extracts (CFs) exhibited optimal inhibitory effects against M pro . We proceeded to use the CF metabolite database to screen natural M pro inhibitors by combining virtual screening and biochemical assays. We identified that several CF natural products, including astragalin, myricitrin, and astilbin, significantly inhibited M pro with half-maximal inhibitory concentrations (IC50s) of 0.13, 10.73, and 7.92 μ m , respectively. These findings may serve as a basis for further studies into the suitability of cotton as a source of potential therapeutics for SARS-CoV-2.
危险品化学品经营许可证（带存储）