Isolation and expression of a new high molecular weight glutenin subunit gene at the Glu-D-1-2 locus from Aegilops tauschii

Zhang, Y. and An, X. and Li, X. and Chen, S. and Gao, L. and Wang, K. and Wang, S. and Yan, Y. (2009) Isolation and expression of a new high molecular weight glutenin subunit gene at the Glu-D-1-2 locus from Aegilops tauschii. Cereal Research Communications, 37 (3). pp. 449-457. ISSN 0133-3720

Text crc.37.2009.3.14.pdf Restricted to Repository staff only until 30 September 2029. Download (733kB)

Abstract

Two new y-type HMW-GSs in Ae. tauschii , 1Dy12.1* ^t and 1Dy12.2 ^t with the mobility order of 1Dy12.2 ^t > 1Dy12.1* ^t > 1Dy12.1 ^t >1Dy12, were identified by both SDS-PAGE and MALDI-TOF-MS. Molecular cloning and sequencing showed that the genes encoding subunits 1Dy12.1* ^t and 1Dy12.2 ^t had identical nucleotide acid sequences with 1,947 bp encoding a mature protein of 627 residues. Their deduced molecular weights were 67,347.6 Da, satisfactorily corresponding to that of 1Dy12.2 ^t subunit determined by MALDI-TOF-MS (67,015.7 Da), but was significantly smaller than that of the the 1Dy12.1* ^t subunit (68,577.1 Da). Both subunits showed high similarities to 1Dy10, suggesting that they could have a positive effect on bread-making quality. Interestingly, the expressed protein of the cloned ORF from accessions TD87 and TD130 in E. coli co-migrated with subunit 1Dy12.2 ^t , but moved slightly faster than 1Dy12.1* ^t on SDS-PAGE. The expressed protein in transgenic tobacco seeds, however, had the same mobility as the 1Dy12.1* ^t subunit, as confirmed by both SDS-PAGE and Western blotting. Although direct evidence of phosphoprotein could not be obtained by specific staining method, certain types of post-translational modifications (PTMs) of the 1Dy12.1* ^t subunit could not be excluded. We believe PTMs might be responsible for the molecular weight difference between the subunits 1Dy12.1* ^t and 1Dy12.2 ^t .

Actions (login required)

Edit Item