Poster: Hormones

Abs # 623: Identification of absicsic acid inducible genes in wheat by mRNA differential display

Presenter:	Keskin, Birsen C, birsen@rigeb.gov.tr
Authors	Keskin, Birsen C (A)   Memon, Abdul R (A) (B)
Affiliations:	(A): TUBITAK, Inst Genetic Engineering & Biotech (B): Ylidiz Technical University, Dept. Biology

Abscisic acid (ABA) is one of the major phytohormone in plants. It plays an important role during plant growth and development. A large number of stress related genes are expressed by ABA. These ABA-mediated stress responses are critical to plant survival and productivity. mRNA differential display technique was used to identify ABA induced genes in wheat. Drought sensitive (Atay 85) and resistant (Sivas 111/33 and Gerek 79) wheat variaties were selected from wheat breeding stations and were subjected with different ABA treatments (Control, 50 mM, 100 mM, 200 mM) for 30 days. Total RNA was isolated by Guanidin-HCl and reverse transcribed with an anchored oligo-dT11 primers. The products were amplified in the presence of 33P-a–dATP and several differentially expressed transcripts were identified after seperation of the cDNA products in a denaturing polyacrilyamide (Diffrential Display) gel. 34 differentially expressed cDNA fragments were determined and around 10 cDNA fragments were reamplified and cloned into pCR-TRAP vector. Double stranded plasmid DNAs were sequenced by either manually or by automated DNA sequencer. Gene data bank analysis revealed that, one of the sequenced cDNA fragments was around 50% identical to Zea mays Mitogen-activated protein kinase 4 (MAPK-4). MAPK cascades plays an important role in mediating stress responses in plants and is one of the well characterized intracellular signalling modules and is highly conserved among eukaryotes. For the isolation of full length cDNA clone, Atay cDNA library is being screened. The expression studies of this transcript is also being carried at mRNA level with several drought sensitive and resistant wheat varieties treated with 100 mM ABA.