梭梭WOX转录因子家族鉴定及HaWOX29和HaWOX54在根生长中的功能研究OA

The desert plant Haloxylon ammodendron,commonly known as sorghum or saxaul,has a well-developed root system characterized by lateral roots that are capable of parasitizing the traditional Chinese medicine plant Cistanche deserticola.This trait endows H.ammodendron with significant ecological and economic value for desert management and for the social development of desert regions.In plants,WOX transcription factors play a crucial role in the growth and development of roots.In this study,we identified 64 members of the WOX transcription factor family from the H.ammodendron genome.Building upon previous transcriptome analysis results,we screened and cloned the genes HaWOX29 and HaWOX54,which exhibited high transcript levels in the roots.Quantitative PCR analysis indicated that the transcript levels of HaWOX29 and HaWOX54 were obvious higher in roots than in other tissues,and that both of these genes were down-regulated under drought,salt,and high-temperature stresses.Conversely,they were up-regulated under low-temperature conditions and treatments with various hormones,namely indole-3-acetic acid,abscisic acid,and salicylic acid.Through Agrobacterium-mediated transformation,we obtained plants overexpressing HaWOX29 and HaWOX54.Phenotypic and root scanning analyses revealed that the average primary root length of the HaWOX29-overexpressing plants was 2.49-times than that of the control group(transformed with the empty vector).The primary roots of the HaWOX54-overexpressing plants were 2.08-times longer than those of the control group,and the average root branching number was 4.34-times greater.Thus,we concluded that HaWOX29 may facilitate the elongation of primary roots in H.ammodendron,while HaWOX54 may be implicated in the development of lateral roots and the elongation of primary roots.The results of this study identify WOX transcription factors associated with the growth and development of H.ammodendron roots,offering theoretical and practical guidance for investigating the molecular mechanisms underlying root development and for screening superior germplasm resources of H.ammodendron.