Decreasing detection frequency of MITE (MCLas-A) in the population of 'Candidatus Liberibacter asiaticus' recently collected in southern China

摘要

An active miniature inverted-repeat transposable element(MITE),MCL as-A,was previously identified from'Candidatus Liberibacter asiaticus'known to be associated with citrus Huanglongbing(HL B,yellow shoot disease).To explore the recent transposition status of MCLas-A,389'Ca.L.asiaticus'strains collected from nine regions in China were amplifed using a specific primer set and three representative'Ca.L.asiaticus'strains were analyzed by next-generation sequencing(NGS)approach.PCR and genomic analysis showed that the entire MCLas A was only present in 1.80%(7/389)and the jumping-out type of the MITE was predominant(8123%)in samples tested,suggesting high frequency transposition occurred in'Ca.L.asiaticus'strains recently collected from China.Biological roles of transposition of the active MITE remain to be determined.