YAKUBOV, BAKHTIYOR1*, AVIV SHACHACK2, ODED SHOSEYOV2, and AVI GOLAN-GOLDHIRSH1. 1Ben-Gurion University of The Negev, The Blaustein Institute for Desert Research, Desert Plant Biotechnology Laboratory, Sede boqer Campus 84990 Israel; 2The Hebrew University of Jerusalem, The faculty of agriculture Rehovot, The Kennedy-Leigh center for Horticultural Research, and the Otto warburg center for Agricultural Biotechnology, P.O.B 12, Rehovot, 76100, Israel. - Molecular cloning and characterization of the Pistacia vera dehydrin gene.
A full length dehydrin cDNA clone was obtained from a Pistacia vera L.
cDNA library. It was sequenced and the deduced protein consisted of
230 amino acids with a molecular weight of 25,870 kDa. The protein is
glycine rich and highly hydrophilic and contains 47.39% charged amino
acids. It contains 5 repeats of the characteristic K-box, but no
serine tract and no Y segment, characteristic of certain dehydrins.
The transcript consisted of additional 5 repetitive sequences, 20-22
nucleotides long, on the N-terminus side of the K-box and adjacent to
it. A similar pattern of repetitive units was also detected in other
dehydrins of deciduous trees, as well as other dehydrins which belong
to the Kn-type. Accumulation of the dehydrin transcripts precedes
the accumulation of the protein, which stays high in the inflorescence
bud throughout winter. The protein accumulates in the outer leaves
(scales) of the inflorescence bud and in the bark. It was mostly
concentrated in the palisade-like cells underneath the epidermis. It
appears like a cytoplasmic protein with no specific organelar
location. It was suggested that the inflorescence bud protein (Ibp)
dehydrin of pistachio may have a dual purpose, in cold tolerance and
in winter storage of nitrogen and carbon for spring growth.
Key words: dehydration stress, dehydrin, dormancy, pistachio Pistacia vera L.