Plants possess remarkable regenerative abilities to form de novo vasculature after damage and in response to pathogens that invade and withdraw nutrients.To identify common factors that affect vascular formation upon ...Plants possess remarkable regenerative abilities to form de novo vasculature after damage and in response to pathogens that invade and withdraw nutrients.To identify common factors that affect vascular formation upon stress,we searched for Arabidopsis thaliana genes differentially expressed upon Agrobacterium infection,nematode infection,and plant grafting.One such gene is cell wall-related and highly induced by all three stresses,which we named ENHANCED XYLEM AND GRAFTING1(EXG1),since its mutations promote ectopic xylem formation in a vascular cell induction system and enhance graft formation.Further observations revealed that exg1 mutants show inhibited cambium development and callus formation but enhanced tissue attachment,syncytium size,phloem reconnection,and xylem formation.Given that bras-sinosteroids also promote xylem differentiation,we analyzed brassinosteroid-related genes and found that mutations in RLP44 encoding a receptor-like protein cause similar regeneration-related phenotypes as mu-tations in EXG1.Like EXG1,RLP44 expression is also induced by grafting and wounding.Mutations in EXG1 and RLP44 affect the expression of many genes in common,including those related to cell walls and genes important for vascular regeneration.Our results suggest that EXG1 integrates information from wounding or pathogen stress and functions with RLP44 to suppress vascular differentiation during regeneration and healing.展开更多
People have grafted plants since antiquity for propagation,to increase yields,and to improve stress tolerance.This cutting and joining of tissues activates an incredible regenerative ability as different plants fuse a...People have grafted plants since antiquity for propagation,to increase yields,and to improve stress tolerance.This cutting and joining of tissues activates an incredible regenerative ability as different plants fuse and grow as one.For over a hundred years,people have studied the scientific basis for how plants graft.Today,new techniques and a deepening knowledge of the molecular basis for graft formation have allowed a range of previously ungraftable combinations to emerge.Here,we review recent developments in our understanding of graft formation,including the attachment and vascular formation steps.We analyze why plants graft and how biotic and abiotic factors influence successful grafting.We also discuss the ability and inability of plants to graft,and how grafting has transformed both horticulture and fundamental plant science.As our knowledge about plant grafting improves,new combinations and techniques will emerge to allow an expanded use of grafting for horticultural applications and to address fundamental research questions.展开更多
基金S.M.and C.W.M.were supported by a Vetenskapsra det grant(2017-05122)A.Z.and C.W.M.were supported by a Wallenberg Academy Fellowship(2016-0274)+2 种基金F.A.,C.M.and C.W.M.were supported by a European Research Council starting grant(GRASP-805094)M.S.A.and P.M.were supported by a Vetenskapsra det grant(2019-05634)an MSCA Postdoctoral Fellowship(101066035-PREENER).
文摘Plants possess remarkable regenerative abilities to form de novo vasculature after damage and in response to pathogens that invade and withdraw nutrients.To identify common factors that affect vascular formation upon stress,we searched for Arabidopsis thaliana genes differentially expressed upon Agrobacterium infection,nematode infection,and plant grafting.One such gene is cell wall-related and highly induced by all three stresses,which we named ENHANCED XYLEM AND GRAFTING1(EXG1),since its mutations promote ectopic xylem formation in a vascular cell induction system and enhance graft formation.Further observations revealed that exg1 mutants show inhibited cambium development and callus formation but enhanced tissue attachment,syncytium size,phloem reconnection,and xylem formation.Given that bras-sinosteroids also promote xylem differentiation,we analyzed brassinosteroid-related genes and found that mutations in RLP44 encoding a receptor-like protein cause similar regeneration-related phenotypes as mu-tations in EXG1.Like EXG1,RLP44 expression is also induced by grafting and wounding.Mutations in EXG1 and RLP44 affect the expression of many genes in common,including those related to cell walls and genes important for vascular regeneration.Our results suggest that EXG1 integrates information from wounding or pathogen stress and functions with RLP44 to suppress vascular differentiation during regeneration and healing.
基金supported by a European Research Council starting grant(GRASP-805094)supported by an MSCA Postdoctoral Fellowship(UMOCELF-101069157).
文摘People have grafted plants since antiquity for propagation,to increase yields,and to improve stress tolerance.This cutting and joining of tissues activates an incredible regenerative ability as different plants fuse and grow as one.For over a hundred years,people have studied the scientific basis for how plants graft.Today,new techniques and a deepening knowledge of the molecular basis for graft formation have allowed a range of previously ungraftable combinations to emerge.Here,we review recent developments in our understanding of graft formation,including the attachment and vascular formation steps.We analyze why plants graft and how biotic and abiotic factors influence successful grafting.We also discuss the ability and inability of plants to graft,and how grafting has transformed both horticulture and fundamental plant science.As our knowledge about plant grafting improves,new combinations and techniques will emerge to allow an expanded use of grafting for horticultural applications and to address fundamental research questions.
