This study characterized OsLEA1a, a rice protein gene involved in stress responses in plants and bacteria, and is not directly related to Epitalon research. The protein happens to be rich in amino acids like Ala, Glu, Asp, and Gly but is a distinct plant protein unrelated to the AEDG peptide.
Abstract
OsLEA1a is a late embryogenesis abundant (LEA) protein gene from Oryza sativa L, which contains an open reading frame of 282-bp that encodes a putative polypeptide of 93 amino acids. OsLEA1a protein contains abundant of Lys, Ala, Glu, Asp, Gly, Arg and Leu, but depleted in Cys, His, Phe, Trp and Tyr residues; and is strongly hydrophilic. OsLEA1a includes six helical domains and a β-sheet domain. Real-time PCR analysis showed that OsLEA1a was expressed in roots, leaves and panicles of rice, with no or only a few transcripts in stem tissues, and remained at a relatively higher level in leaves during the tillering period, the heading period, the filling period and the full ripe period. To make sense of OsLEA1a functions, TrxA-OsLEA1a fusion protein expression vector and OsLEA1a protein expression vector were transformed into Escherichia coli DL21 (DE3), respectively. The accumulation of the TrxA-OsLEA1a fusion protein or OsLEA1a protein interfered with the resistance of E. coli to high salinity, metal ions, hyperosmotic, oxidation, heat and freeze-thaw stresses. The purified TrxA-OsLEA1a fusion protein reduced stabilization of LDH and increased damage of diverse abiotic stresses to LDH. The findings suggested that the OsLEA1a may confor antibacterial activity under abiotic stresses.