AP1 — Hordeum vulgare subsp. vulgare

Summary

HORVU.MOREX.R3.5HG0511210, designated HvAP1 (also known as HvVRN1), encodes a MADS-box transcription factor on barley chromosome 5H. The protein contains a MADS-box and K-box domain and exhibits RNA polymerase II transcription regulatory region sequence-specific DNA binding and transcription corepressor activity. HvAP1 is associated with the downregulation and upregulation of the vernalization response, photoperiodism, memory, fruit morphogenesis, inflorescence and floral meristem identity maintenance, integument development, abscission, and auxin transport regulation. It localises to the nucleus, cytosol, and nucleolus. The gene is linked to grain plumpness, spike length, leaf length, stem elongation, days to flowering, photoperiod-sensitive flowering time, and responses to high temperature and UV light. Studies of related genes in other species connect the family to floral organ development, senescence, abscission, grain shape, tillering, and heading date.