CbLEA, a NovelLEA Gene fromChorispora bungeana, Confers Cold Tolerance in Transgenic Tobacco

Abstract

A novel late embryogenesis abundant (LEA) gene (AY804193), named CbLEA, has now been isolated from Chorispora bungeana. This rare alpine subnival plant can survive sudden snowstorms and low temperatures. The full-length CbLEA is 842 bp, with an open reading frame encoding 169 amino acids. The putative molecular weight of CbLEA protein is 17.9 kDa, with an estimated pl of 6.45. To investigate the functioning of this CbLEA protein in cold-stress tolerance, CbLEA was introduced into tobacco under the control of the CaMV35S promoter. Second-generation (R1) transgenic tobacco plants exhibited significantly increased tolerance to cold. These transgenics maintained lower malondialdehyde (MDA) contents and electrolyte leakage (EL) but their relative water content (RWC) was significantly higher compared with non-transgenic plants under chilling stress. Further experimental results showed that non-transgenic plants had severe freezing damage after exposure to -2~ for 1 h, whereas the transgenics suffered only slight injury under the same conditions. Moreover, survival was longer in the latter genotype at that temperature. The extent of increased cold tolerance was positive correlated with the level of CbLEA protein accumulation, and was also reflected by the delayed development of damage symptoms. This indicates that CbLEA is an excellent stress tolerance gene, and holds considerable potential as a new molecular tool for engineering improved plant genetics.

Rice Aldehyde Dehydrogenase7 Is Needed for Seed Maturation and Viability

“…seed development (Bartels et al, 1988;Hartwigsen and Goggi, 2002). Their overexpression enhances tolerance to salt, drought, and osmotic stresses in transgenic plants (Brini et al, 2007;Zhang et al, 2007). Here, we observed that levels of OsALDH7 transcripts started to increase at the late stage of maturation, similar to those of the LEA genes.…”

Piercing and incubation method of in planta transformation producing stable transgenic plants by overexpressing DREB1A gene in tomato (Solanum lycopersicum Mill.)

“…A late embryogenesis abundant (LEA) gene; CbLEA was isolated from Chorispora bungeana and introduced into tobacco whose overexpression exhibited cold tolerance by significantly higher RWC compared with their counterparts. The degree of chilling tolerance in tobacco was associated with high accumulation of CbLEA protein that protected the transgenic plants from cold injury (Zhang et al 2007). Yanez et al (2009) reported that bZIP transcription factor regulated cold inducible gene SlAREB1 and overexpression of this gene played an essential role in cold tolerance accumulating more RWC in Solanum genus.…”