Compound leaf development requires the coordination of genetic factors, hormones, and other signals. In this study, we explored the functions of Class Ⅱ KNOTTED-like homeobox(KNOXII)genes in the model leguminous plan...Compound leaf development requires the coordination of genetic factors, hormones, and other signals. In this study, we explored the functions of Class Ⅱ KNOTTED-like homeobox(KNOXII)genes in the model leguminous plant Medicago truncatula. Phenotypic and genetic analyses suggest that Mt KNOX4, 5 are able to repress leafet formation, while Mt KNOX3, 9, 10 are not involved in this developmental process. Further investigations have shown that Mt KNOX4 represses the CK signal transduction, which is downstream of Mt KNOXⅠ-mediated CK biosynthesis. Additionally,two boundary genes, FUSED COMPOUND LEAF1(orthologue of Arabidopsis Class M KNOX) and NO APICAL MERISTEM(orthologue of Arabidopsis CUP-SHAPED COTYLEDON), are necessary for Mt KNOX4-mediated compound leaf formation.These findings suggest, that among the members of Mt KNOXⅡ, Mt KNOX4 plays a crucial role in integrating the CK pathway and boundary regulators,providing new insights into the roles of Mt KNOXⅡ in regulating the elaboration of compound leaves in M. truncatula.展开更多
基金supported by grants from the National Natural Science Foundation of China (32170833, 31972958 and 32100284)Shandong Province (ZR2020KC018 and ZR202103010073)。
文摘Compound leaf development requires the coordination of genetic factors, hormones, and other signals. In this study, we explored the functions of Class Ⅱ KNOTTED-like homeobox(KNOXII)genes in the model leguminous plant Medicago truncatula. Phenotypic and genetic analyses suggest that Mt KNOX4, 5 are able to repress leafet formation, while Mt KNOX3, 9, 10 are not involved in this developmental process. Further investigations have shown that Mt KNOX4 represses the CK signal transduction, which is downstream of Mt KNOXⅠ-mediated CK biosynthesis. Additionally,two boundary genes, FUSED COMPOUND LEAF1(orthologue of Arabidopsis Class M KNOX) and NO APICAL MERISTEM(orthologue of Arabidopsis CUP-SHAPED COTYLEDON), are necessary for Mt KNOX4-mediated compound leaf formation.These findings suggest, that among the members of Mt KNOXⅡ, Mt KNOX4 plays a crucial role in integrating the CK pathway and boundary regulators,providing new insights into the roles of Mt KNOXⅡ in regulating the elaboration of compound leaves in M. truncatula.