Abstract: 【Objective】 The characteristics of a plasma membrane protein gene TaPM19-1 and its response to abiotic stresses in wheat were studied, which will provide an insight into its biological roles involved in the molecular mechanisms of abiotic-sterss response in wheat. 【Method】 RACE technology was used in full-length cDNA cloning and proper bioinformatics software was applied for characterizing the cloned gene and its deduced protein. Semi-quantitative RT-PCR was performed to study the expression patterns of TaPM19-1 under abiotic stresses. 【Result】 The full-length cDNA of TaPM19-1 is 1 090 bp and no introns were included. TaPM19-1 consists of 182 amino acids with a molecular weight of 19.02 kD, and an typical AWPM19 conserved domain was found in it. Based on the amino acid sequences, 16 AWPM19-like proteins of different plant species were sorted into 3 categories, TaPM19-1 and 3 others, 2 AWMP19-like proteins of Hordeum vulgare and 1 of Brachypodium distachyon, were highly similar and included in the third category. The structural prediction of TaPM19-1 revealed that 4 transmembrane regions with alpha helixes could be formed, the N-terminal (including a signal peptide consists of 27 amino acids) was located inside the membrane, while the C-terminus (about 40 amino acids) located inside. The RT-PCR analysis showed that the expression of TaPM19-1 was not detected in all tissues except in later period of developing seeds. The expression of TaPM19-1 was greatly induced by ABA in roots of two detected wheat cultivars, while its expression in leaves was very low. Under the water stress, the gene was immediately and highly induced both in roots and leaves. The expression of TaPM19-1 can be induced by salt- and heat-stress in Luohan 2, while not induced in Chinese Spring. Under lower temperature treatment, no expression of TaPM19-1 was detected in both wheat varieties. 【Conclusion】 The full-length cDNA of TaPM19-1 was obtained and some typical transmembrane structural features were found in its deduced protein. The expression of TaPM19-1 can be induced by plant hormone ABA. TaPM19-1 can also be induced by drought-, salt- and heat-stress in Luohan 2, while not response to salt- and heat-stress in Chinese Spring. The results suggested that TaPM10-1 might have different transcriptional regulating mechanisms in Luohan 2 and Chinese Spring.

Key words: wheat, plasma membrane protein, gene cloning, abiotic stress, expression