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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.Regulation of gene expression at the level of transcription controls many crucial biological processes including growth and development, stress response, signal transduction and disease resistance. A number of different factors, such as zinc finger protein, are required for the processes of transcription, in which the transcription factors play an important role. In our laboratory, two cDNA libraries from the PEG-treated and non-treated seedling leaves of chickpea XJ209 were constructed and many genes were found to express differentially and involved in diverse biological progresses, such as metabolism, transcription, signal transduction, protein synthesis and others.Herein, three zinc finger protein genes, which were picked out from the cDNA library, were cloned by RACE technology. Bioinformatic analysis and expression profile analysis 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 zinc finger protein gene ZF1 was cloned by RT-PCR and rapid amplification of cDNA ends (RACE). ZF1 didn’t include intron and encoded a 26.33 kDa protein with 244 amino acids, which contained two typical C2H2 zinc finger domains. The deduced protein sequence had a potential nuclear localization signal (NLS). Meanwhile, Transient expression of the ZF1-GFP protein in onion epidermal cells showed that ZF1 protein was localized in cell nuclei. Semi-quantitative RT-PCR analysis showed that ZF1 was expressed in root, stem, leaf, flower, immature pod and embryo of chickpea. ZF1 showed variational expression during germination. The expression of ZF1 investigated by semi-quantitative PCR had no obvious change in stresses of cold, salt, wounding, while was increased at different time under the treatments of heat and drought, as well as N-6-benzyl-adenine (6-BA), abscisic acid (ABA), ethephon (Et), gibberellin (GA3), indole-3-acetic acid (IAA), methyl jasmonate (MeJA), salicylic acid (SA), and H2O2. These results from semi-quantitative PCR of several treatments were further confirmed to be mainly in accord with those from real-time quantification PCR. Our results suggest that ZF1 may play multiple roles in abiotic and biotic resistance pathways, as well as in plant growth.ZF2 didn’t include intron and encoded a 25.30 kDa protein with 232 amino acids, which contained two typical C2H2 zinc finger domains. Semi-quantitative RT-PCR analysis showed that ZF2 was expressed in root, stem, leaf, flower, immature pod and embryo of chickpea. ZF2 showed variational expression during germination. semi-quantitative PCR analysis indicated that the expression of ZF2 could be induced by drought, heat, salt, H2O2, abscisic acid (ABA), salicylic acid (SA), N-6-benzyl-adenine (6-BA), ethephon (Et) and indole-3-acetic acid (IAA). These results from semi-quantitative PCR of several treatments were further confirmed to be mainly in accord with those from real-time quantification PCR. Our results suggest that ZF2 may play multiple roles in abiotic and biotic resistance pathways, as well as in plant growth..ZF3 didn’t include intron and encoded a 42.9 kDa protein with 385 amino acids, which contained two typical CCCH zinc finger domains. Semi-quantitative RT-PCR analysis showed that ZF3 was expressed in root, stem, leaf, flower, immature pod and embryo of chickpea. ZF3 showed variational expression during germination. semi-quantitative PCR analysis indicated that the expression of ZF3 could be induced by drought, cold, salt, H2O2, N-6-benzyl-adenine (6-BA), salicylic acid (SA), abscisic acid (ABA), ethephon (Et), indole-3-acetic acid (IAA), and methyl jasmonate (MeJA),,while heat treatment decreased the levels of ZF3 mRNA. These results from semi-quantitative PCR of several treatments were further confirmed to be mainly in accord with those from real-time quantification PCR. Transient expression of the ZF3-GFP protein in onion epidermal cells showed that ZF3 was localized in cell nuclei. Our results suggest that ZF3 may play multiple roles in abiotic and biotic resistance pathways, as well as in plant growth.
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