Characterization of promoter sequence and identification of interacting partners of ABI3 in chickpea (Cicer arietinum L.)
Student name: Ms Apoorva Gupta
Guide: Dr Anandita Singh
Year of completion: 2018
Host Organisation: National Institute of Plant Genome Research (NIPGR), New Delhi
Supervisor (Host Organisation): Dr Sabhyata Bhatia
Abstract: The nutritional quality of chickpea seeds depends on the seed storage proteins (SSPs) accumulated
in the cotyledons during seed maturation. This accumulation of SSPs is controlled by several
transcription factors (TFs) acting in a combinatorial manner. Despite extensive studies, this
regulatory assembly needs further characterization in many crop plants including chickpea. ABI3,
along with other proteins or transcription factors, regulates various aspects of seed maturation.
ABI3 can interact with its promoter either directly or through certain unknown interacting
partners, and knowledge of these interacting partners will help understand the mechanism of seed
filling. In the present work, 2kb promoter sequence of ABI3 was analysed in-silico and many
important cis-regulatory elements like SEF4, AMYBOX, E-BOX, MYB, MYC, WRKY7 etc. were
found to be present. Many TF binding sites such as DOF core, TATA box, CAAT box, RAV1, I-box
and W-box were also observed. Deletion sequences of 2kb, 1kb and 500bp regions of the promoter
were cloned into pBI101 vector to analyse the GUS expression driven by ABI3 promoter sequence.
Transgenic Arabidopsis seedlings were successfully obtained for the 500bp region of the promoter.
Analysis of interactions between ABI3 and its putative interacting partners using yeast-two-hybrid
assay revealed that the interactions are very weak or the hybrid proteins are not expressing stably
in the host cell and therefore need further confirmation through another approach. In conclusion,
this study helped characterize the ABI3 gene and its promoter. These results will provide a useful
resource to explore the regulatory networks of ABI3 in chickpea seed development and for their
further experimental characterization.
Keywords: Chickpea, SSPs, ABI3, Y2H, promoter-analysis
