Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Via Celoria 26, 20133 Milano, Italy.
Plant J. 2009 Nov;60(4):626-37. doi: 10.1111/j.1365-313X.2009.03985.x. Epub 2009 Jul 25.
During the initial stages of flower development, floral meristems increase in size without the formation of floral organs. When a critical meristem size is reached, the floral meristem begins to develop the floral organs. The first stages of flower development are characterized by the expression of genes such as Apetala 1 (AP1), cauliflower (CAL), AGAMOUS-LIKE 24 (AGL24) and short vegetative phase (SVP). We have shown that AP1, AGL24 and SVP act redundantly to control the identity of the floral meristem and to repress expression of class B, C and E genes. Recently, it was shown that class E gene repression was direct and established by two independent pathways. We show here that repression of class B and C genes is also directly established by a co-repressor complex that comprises LEUNIG (LUG), SEUSS (SEU) and the MADS box dimers AP1-AGL24 and AP1-SVP. Furthermore, we show that the distantly related suppressor of overexpression of CO 1 (SOC1) MADS box gene can complement for the loss of AGL24 and SVP activity; however, under normal conditions, this transcription factor does not play a role during the early stages of flower development.
在花发育的初始阶段，花分生组织在不形成花器官的情况下增大。当达到临界分生组织大小时，花分生组织开始发育花器官。花发育的最初阶段的特征是表达基因，如 APETALA1(AP1)、花椰菜(CAL)、AGAMOUS-LIKE24(AGL24)和短营养期( SVP)。我们已经表明，AP1、AGL24 和 SVP 冗余地起作用以控制花分生组织的身份并抑制 B 类、C 类和 E 类基因的表达。最近，表明 E 类基因的抑制是直接的，并通过两条独立的途径建立。我们在这里表明，B 类和 C 类基因的抑制也是由包含 LEUNIG(LUG)、SEUSS(SEU)和 MADS 盒二聚体 AP1-AGL24 和 AP1-SVP 的共抑制复合物直接建立的。此外，我们表明，远亲的 CO1 过表达抑制因子(SOC1)MADS 盒基因可以弥补 AGL24 和 SVP 活性的丧失;然而，在正常情况下，这种转录因子在花发育的早期阶段不起作用。
