Cloning and expression of zinc finger protein gene ZF1 in chickpea (Cicer arietinum L.).

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 factors, such as C2H2 zinc finger protein, are required and factors play an important role in the transcription. Chickpea (Cicer arietinum L.) is the third important legume crop gown mainly in the arid and semi-arid regions in the world. Due to its taxonomic proximity with the model legume genome of Medicago truncatula and its ability to grow in soil with relatively low water content, chickpea is being investigated as a model legume crop for drought tolerance studies. 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 biologi-cal processes, such as metabolism, transcription, signal transduction, protein synthesis and others. According to an EST in the cDNA libraries, a zinc finger protein gene ZF1 was cloned by RT-PCR and rapid amplification of cDNA ends (RACE). ZF1 did not include any intron, encoding a 26.33 kD protein with 244 amino acids, containing two typical C2H2 zinc finger domains. The deduced protein sequence had a potential nuclear localization signal (NLS). Meanwhile, transient expression of the ZF1-GFP pro-tein in onion epidermal cells showed that ZF1 protein was localized in cell nuclei. Semi-quantitative RT-PCR analysis showed that ZF1 expressed in root, stem, leaf, flower, immature pod, and embryo of chickpea with different expression patterns. The expres-sion of ZF1 investigated by semi-quantitative PCR had no obvious changes under stresses of cold, salt and wounding, while was increased 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 in 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.