MSI1 — Arabidopsis thaliana

Summary

AT5G58230 (MSI1) in Arabidopsis thaliana encodes a WD40 repeat-containing protein of the RBAP46/RBAP48/MSI1 family, associated with histone H3K27 trimethylase activity, chromatin binding, and nucleic acid binding. MSI1 is linked to cell-cell fusion, DNA imprinting, heterochromatin organization, regulation of stem cell population maintenance, and short-day photoperiodism. Observed phenotypes connect it to parthenogenetic embryo development, reproductive development, homeotic gene expression, heterochromatin formation, and drought stress response. The gene is also associated with traits such as seed weight, seed volume, carpel number, leaf width, stem number, phosphorus concentration, and photoperiod sensitivity. MSI1 localizes to PcG protein complexes, chromatin silencing complexes, euchromatin, heterochromatin, and ubiquitin ligase complexes, and participates in pathways including cell cycle, G1/S transition, and reproductive meristem phase change.