Rho/Racofplant(ROP)GTPases是一种植物特异性蛋白质,可作为分子开关,由鸟嘌呤核苷酸交换因子(GEF)激活,并由GTP酶激活蛋白(GAP)灭活。苔藓植物Marchantiapolymorpha包含ROP(MpROP)的单拷贝,GEF(ROPGEF和SPIKE(SPK)),和差距(ROPGAP和ROP增强器(REN))。MpROP调节各种组织和器官的发育,如根状体,Gemmae,和空气室。而ROPGEF,KARAPPO(MpKAR)对于宝石启动至关重要,对其他ROP调节因子的功能了解较少。本研究集中于两个GAP:MpROPGAP和MpREN。Mpren单突变体在叶状体生长中显示出缺陷,根状茎尖生长,gemma发展,和气室的形成,而Mpropgap突变体没有显示出可见的异常。然而,MpropgapMpren双突变体比Mpren单突变体具有更严重的表型,建议MpROPGAP在涉及MpREN的进程中的备份角色。MpROPGAP的过表达,MpREN导致类似的配子体缺陷,强调MpROP激活/失活循环(或平衡)的重要性。因此,MpREN主要是,和MpROPGAP作为备份,调节配子体发育,最有可能通过控制多形性分枝杆菌中的MpROP激活。
Rho/Rac of plant (ROP) GTPases are a plant-specific proteins that function as molecular switches, activated by guanine nucleotide exchange factors (GEFs) and inactivated by GTPase-activating proteins (GAPs). The bryophyte Marchantia polymorpha contains single copies of ROP (MpROP), GEFs (ROPGEF and SPIKE (SPK)), and GAPs (ROPGAP and ROP ENHANCER (REN)). MpROP regulates the development of various tissues and organs such as rhizoids, gemmae, and air chambers. While the ROPGEF, KARAPPO (MpKAR) is essential for gemma initiation, the functions of other ROP regulatory factors are less understood. This study focused on two GAPs: MpROPGAP and MpREN. Mpren single mutants showed defects in thallus growth, rhizoid tip growth, gemma development, and air chamber formation, whereas Mpropgap mutants showed no visible abnormalities. However, Mpropgap Mpren double mutants had more severe phenotypes than the Mpren single mutants, suggesting backup roles of MpROPGAP in MpREN-involving processes. Overexpression of MpROPGAP, MpREN resulted in similar gametophyte defects, highlighting the importance of MpROP activation/inactivation cycling (or balancing). Thus, MpREN predominantly, and MpROPGAP as a backup, regulate gametophyte development, most likely by controlling MpROP activation in M. polymorpha.