Cloning, Expression And Subcellular Localization Of Two Lea Protein Genes,Carlea793and Carlea4, In Chickpea (Cicer Arietinum L.)

Chickpea (Cicer arietinum L.) is the third important legume crop grown mainly in the arid and semi-arid regions. Due to its taxonomic proximity with the model legume genome Medicago truncatula and its ability to grow in soil with relatively low water content, chickpea has its unique advantage to understand how plant responds to drought stress. To deal with the diverse stresses, plants will produce many responsive reaction and inducible proteins with the ability of resistant to stress, of which LEA proteins are an important group.Here, two LEA protein genes, which were picked out from the cDNA library from treated seedlings with PEG, were cloned by RACE technology. Bioinformatic and expression profile analyses were conducted to further understand the molecules and their function in many crucial biological processes including growth and development, stress response, signal transduction and disease resistance.A lea protein gene CarLEA793was cloned by RT-PCR and rapid amplification of cDNA ends (RACE). CarLEA793didn’t contain intron and encoded a24.02kDa protein with226amino acids, which contained a LEA-like protein domain. Transient expression of the CarLEA793::GFP protein in onion epidermal cells showed that CarLEA793protein was localized in cell nuclei. Semi-quantitative RT-PCR analysis showed that CarLEA793was expressed in root, stem, leaf, flower, immature pod and embryo of chickpea. Real-time quantitative PCR analysis indicated that CarLEA793showed variational expression during germination. In leaf, the expression of CarLEA793investigated by semi-quantitative PCR was induced at different time under the treatments of drought, GA3, MeJA, salinity, ABA, cold, heat, but had no obvious change in stress of IAA, while in the root, CarLEA793was increased at different time under the treatments of IAA, cold, MeJA and heat, had not obvious change in stresses of drought, salinity and ABA. These results from semi-quantitative PCR of several treatments were further confirmed to be mainly in accord with those from real-time quantitative PCR. Our results suggest that CarLEA793may play multiple roles in abiotic and biotic resistance pathways, as well as in plant growth.CarLEA4contained one155bp intron and encoded a15.75kDa protein with152amino acids, which contained a typical LEA-1protein domain. Semi-quantitative RT-PCR analysis showed that CarLEA4was expressed in root, stem, leaf, flower, immature pod and embryo of chickpea. CarLEA4showed variational expression during germination. Semi-quantitative RT-PCR analysis showed that the expression of CarLEA4could be induced by drought, salinity, IAA, ABA and MeJA, while was inhibited by heat in leaf. Meanwhile, in root, CarLEA4was increased at different time under the treatments of drought, salinity, ABA, and was inhibited by MeJA, cold and IAA. These results from semi-quantitative PCR of several treatments were further confirmed to be mainly in accord with those from real-time quantitative PCR. Our results suggest that CarLEA4may play multiple roles in abiotic and biotic resistance pathways, as well as in plant growth.