Cloning and Expression Analysis of the Subunit HvMu3 of Adaptor Complexes AP-3 from Barley

In this study the μ3 subunit gene HvMu3,subunit μ3 of complexes AP3 from barley(Hordeum vulgare) was isolated with RT-PCR using a pair of primers designed based on simulation of gene splicing and the conserved amino acid sequence of the Mu3 subunits.Semi-quantitative RT-PCR and q-PCR assay were performed to examine tissue expression of HvMu3 during NaCl,ABA and Cr6+ stress treatments.The results showed that:(1) HvMu3 contained a 4 439 bp long complete open reading frame including 8 exons and 7 introns,and encoded 417 amino acid residues containing a MHD domain,the typical characteristics of Mu3 3 subunits.(2) As displayed by semi-quantitative RT-PCR and q-PCR assay,HvMu3 was expressed in all tissues,and its expression level was high in the embryo and root,suggesting a close relationship between the expression of this gene and the development of barley.(3) The expression profiling also showed that HvMu3 was up-regulated by ABA,NaCl and Cr6+ stresses in the seedlings.