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bioRxiv · 10.1101/2021.11.05.467508

Biochemical analysis of deacetylase activity of rice sirtuin OsSRT1, a class IV member in plants

Dey, S.·Mitra, N.
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Abstract

The role of plant sirtuins is slowly unwinding. There are only reports of H3K9Ac deacetylation by OsSRT1. This belongs to class IV sirtuin family with a longer C-terminus. Here C-terminus is required for ligand binding and catalysis. OsSRT1 can deacetylate the lys residues at the N terminal tail of both H3 and H4. It can also target the non-histone target, OsPARP1 playing a role in DNA damage repair pathway. Changes in the extent of different histone deacetylation by OsSRT1 is also related with different abiotic stress conditions. NAM and ADP-ribose has negative effect on OsSRT1 deacetylation. HighlightsO_LIOsSRT1 is capable of deacetylating various lysine residues of histone H3 and H4 as well as OsPARP1. C_LIO_LIThe extra long C-terminus of OsSRT1 is required for its substrate binding and thus, its catalysis. C_LIO_LIOn plants exposure to H2O2 and Arsenic toxicity, there is a relationship between increased expression of OsSRT1 and increased deacetylation of H3 and H4. C_LI

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Dey, S., Mitra, N.. 2021-11-06. Biochemical analysis of deacetylase activity of rice sirtuin OsSRT1, a class IV member in plants. https://doi.org/10.1101/2021.11.05.467508

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