枣Dicer-like蛋白基因家族鉴定与表达分析

Juvenile jujube witches'broom disease(JWBD)is a severe phytopathogenic disorder that has exhibited an escalating incidence in recent years,posing significant constraints on the development of the jujube industry.The plant Dicer-like(DCL)protein,belonging to the Ribonuclease III(RNase III)enzyme family,represents an indispensable component in plant defense against viral infections.Functioning within the RNA interference(RNAi)pathway,the DCL protein facilitates the conversion of viral nucleic acids into small interfering RNA(siRNA),exerting critical roles in various aspects such as RNA degradation,post-transcriptional gene expression modulation,and antiviral responses.Pathogens have evolved mechanisms to antagonize RNA silencing,thereby subverting the host plant's antiviral defense machinery and promoting the manifestation of disease symptoms.The present study aims to elucidate the involvement of DCL proteins in the pathogenesis of JWBD through comprehensive identification and expression analysis of the jujube DCL gene family.By uncovering the pivotal genes closely associated with disease development,this research endeavors to enhance our understanding of the underlying molecular mechanisms driving JWBD.The findings of this investigation hold the potential to provide valuable scientific insights for the effective management of JWBD in jujube trees,ultimately fostering the sustainable advancement of the jujube industry.The jujube DCL gene family members were identified utilizing high-throughput whole-genome sequencing data of jujube.Subsequently,comprehensive bioinformatics analyses were performed on the acquired gene set.Alignment of the jujube ZjDCLs protein sequences with the homologous counterparts from Arabidopsis(AtDCLs)facilitated the construction of a robust phylogenetic tree,enabling the inference of their evolutionary relationships.Moreover,leveraging transcriptome-wide sequencing data,a comprehensive examination of the temporal gene expression profiles during distinct stages of jujube pathogen infection was conducted.The expression patterns of ZjDCLs were further validated through quantitative real-time polymerase chain reaction(qRT-PCR)analysis,providing valuable insights into their transcriptional dynamics.A total of 11 jujube DCL genes(ZjDCLs)were identified and named based on their sequential positions on the jujube chromosomes,ranging from ZjDCL1 to ZjDCL11.The ZjDCLs were categorized into four classes,namely DCL1,DCL2,DCL3,and DCL4.Physicochemical property analysis revealed that the molecular weight of ZjDCL proteins ranged from 15,217.48 to 225,623.49 Da,while the isoelectric points varied from 5.82(ZjDCL11)to 9.05(ZjDCL2).Chromosomal localization analysis of the ZjDCL genes illustrated their non-uniform distribution across the six jujube chromosomes,with the highest representation observed on chromosome 1.After infection with Jujube Phytoplasma,the expression pattern of Jujube DCL protein changed,indicating that it played a very important role in the response of Jujube to the invasion of Jujube Phytoplasma.