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  • LEAFY and APETALA1 down-regulate ZINC FINGER PROTEIN 1 and 8 to release their repression on class B and C floral homeotic genes
Title: LEAFY and APETALA1 down-regulate ZINC FINGER PROTEIN 1 and 8 to release their repression on class B and C floral homeotic genes
Organ initiation from the shoot apical meristem first gives rise to leaves during vegetative development and then flowers during reproductive development.LEAFY(LFY) is activated after floral induction and together with other factors promotes the floral program. LFY functions redundantly with APETALA1 (AP1) to activate the class B genesAPETALA3(AP3) andPISTILLATA(PI), the class C geneAGAMOUS(AG), and the class E geneSEPALLATA3, which leads to the specification of stamens and carpels, the reproductive organs of flowers. Molecular and genetic networks that control the activation ofAP3,PI,andAGin flowers have been well studied; however, much less is known about how these genes are repressed in leaves and how their repression is lifted in flowers. Here, we showed that two genes encodingArabidopsisC2H2 ZINC FINGER PROTEIN (ZFP) transcription factors, ZP1 and ZFP8, act redundantly to directly repressAP3,PI,andAGin leaves. AfterLFYandAP1are activated in floral meristems, they down-regulateZP1andZFP8directly to lift the repression onAP3,PI,andAG. Our results reveal a mechanism for how floral homeotic genes are repressed and derepressed before and after floral induction.  more » « less
Award ID(s):
1947274
PAR ID:
10497861
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
PubMed Central
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
120
Issue:
22
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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