Abstract:
Using cDNA from
Rehmannia glutinosa leaf as template, a 972 bp fragment of expansin gene which containing a 762 bp ORF that encoded 253 amino acids, was cloned, named
RgEXPA10, which GenBank accession number for this gene is KF011918. A 1 207 bp genomic sequence of
RgEXPA10 was amplified by PCR with leaf DNA as template, sequencing analysis revealed that three exons and two introns in
RgEXPA10 genomic sequence, and which GenBank accession number is KF011919. Molecular and bioinformatic analyses indicated that RgEXPA10 protein have DPBB_1 and Pollen_allerg_1 domain, also including a 26 aa nuclear localization signal and a 19 aa transmembrane region. Phylogenetic analysis revealed that RgEXPA10 showed the highest homology with AtEXPA8 among the 26
α-expansins in
Arabidopsis thaliana. However, the RgEXPA10 indicated the highest homology with the expansin from
Solanum lycopersicum among 22 plant species. Expression patterns using qRT-PCR analysis showed that
RgEXPA10 mainly expressed in unfolded leaf, followed by the tuberous root at stage of expanding period, and rarely expressed in senescing leaf. And
RgEXPA10 showed higher expression level in tuberous root at 60 and 90 days after emergence. The transcription level of
RgEXPA10 significantly reduced under all the three stresses including continuous cropping conditions, salinity and waterlogging. This study will lay foundations for molecular function in development and regulation of different stresses for
R. glutinosa.