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The Roles of the PSEUDO-RESPONSE REGULATORs in Circadian Clock and Flowering Time in Medicago truncatula.

ABSTRACT: PSEUDO-RESPONSE REGULATORs (PRRs) play key roles in the circadian rhythms and flowering in plants. Here, we identified the four members of the PRR family in Medicago truncatula, including MtPRR9a, MtPRR9b, MtPRR7 and MtPRR5, and isolated their Tnt1 retrotransposon-tagged mutants. They were expressed in different organs and were nuclear-localized. The four MtPRRs genes played important roles in normal clock rhythmicity maintenance by negatively regulating the expression of MtGI and MtLHY. Surprisingly, the four MtPRRs functioned redundantly in regulating flowering time under long-day conditions, and the quadruple mutant flowered earlier. Moreover, MtPRR can recruit the MtTPL/MtTPR corepressors and the other MtPRRs to form heterodimers to constitute the core mechanism of the circadian oscillator.

SUBMITTER: Wang X

PROVIDER: S-EPMC10706769 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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The Roles of the PSEUDO-RESPONSE REGULATORs in Circadian Clock and Flowering Time in Medicago truncatula.

Wang Xiao X Zhang Juanjuan J Liu Xiu X Kong Yiming Y Han Lu L

International journal of molecular sciences 20231128 23

PSEUDO-RESPONSE REGULATORs (PRRs) play key roles in the circadian rhythms and flowering in plants. Here, we identified the four members of the PRR family in Medicago truncatula, including MtPRR9a, MtPRR9b, MtPRR7 and MtPRR5, and isolated their Tnt1 retrotransposon-tagged mutants. They were expressed in different organs and were nuclear-localized. The four MtPRRs genes played important roles in normal clock rhythmicity maintena ...[more]

PMID: 38069157

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