With the exception of rice, little is known about the existence of respiratory burst oxidase homolog （rboh） gene in cereals. The present study reports the cloning and analysis of a novel rboh gene, termed ZmrbohB, f...With the exception of rice, little is known about the existence of respiratory burst oxidase homolog （rboh） gene in cereals. The present study reports the cloning and analysis of a novel rboh gene, termed ZmrbohB, from maize （Zea mays L.）. The full-length cDNA of ZmrbohB encodes a 942 amino acid protein containing all of the respiratory burst oxidase homolog catalytically critical motifs. Alternative splicing of ZmrbohB has generated two transcript isoforms, ZmrbohB-α and -β. Spliced transcript ZmrbohB-β retains an unspliced intron 11 that carries a premature termination codon and probably leads to nonsense-mediated mRNA decay. Expression analysis showed that two splice isoforms were differentially expressed in various tissues and at different developmental stages, and the major product was ZmrbohB-e. The transcripts of ZmrbohB-α accumulated markedly when the maize seedlings were subjected to various abiotic stimuli, such as wounding, cold （4℃）, heat （40℃）, UV and salinity stress. In addition, several abiotic stimuli also affected the alternative splicing pattern of ZmrbohB except wounding. These results provide new insight into roles in the expression regulation of plant rboh genes and suggest that ZrnrbohB gene may play a role in response to environmental stresses.展开更多
基金Supported by the State Key Basic Research and Development Plan of China (2003CB114302)the National Natural Science Foundation of China (30571122).
文摘With the exception of rice, little is known about the existence of respiratory burst oxidase homolog （rboh） gene in cereals. The present study reports the cloning and analysis of a novel rboh gene, termed ZmrbohB, from maize （Zea mays L.）. The full-length cDNA of ZmrbohB encodes a 942 amino acid protein containing all of the respiratory burst oxidase homolog catalytically critical motifs. Alternative splicing of ZmrbohB has generated two transcript isoforms, ZmrbohB-α and -β. Spliced transcript ZmrbohB-β retains an unspliced intron 11 that carries a premature termination codon and probably leads to nonsense-mediated mRNA decay. Expression analysis showed that two splice isoforms were differentially expressed in various tissues and at different developmental stages, and the major product was ZmrbohB-e. The transcripts of ZmrbohB-α accumulated markedly when the maize seedlings were subjected to various abiotic stimuli, such as wounding, cold （4℃）, heat （40℃）, UV and salinity stress. In addition, several abiotic stimuli also affected the alternative splicing pattern of ZmrbohB except wounding. These results provide new insight into roles in the expression regulation of plant rboh genes and suggest that ZrnrbohB gene may play a role in response to environmental stresses.
