| Summary: | 碩士 === 國立臺灣大學 === 農業化學系 === 81 === Rice prolamin is a group of storage proteins encoded by
a complex mutigene family. These proteins have
molecular weight in the range of 12 to 17 kDa. in order to
investigate the expression and regulation of rice
prolamin genes , a prolamin cDNA clone pS23 was used as a
probe to screen a rice lambda EMBL 3 genomic library .
Five positive plaques were isolated and phage DNA from one
of the plaques, lambda G601, was purified and digested
with Sal I. A Sal I fragment about 2.6 kb was found to
hybridize to pS23 probe in Southern blotting . The Sal I
fragment was subcloned into pBluescript SK II vecter to
create recombinant plasmids. Two clones, pJM3 and pJM4 ,
were isolated from the recombinant plasmids . DNA mapping
indicated that the inserts in these two clones had
different orientation. Both pJM3 and pJM4 plasmids were cleved
with Xho I and Kpn I , serially deleded by exonuclease III, S1
nuclease digestion , religated and tranformed into XL1-Blue .
This clustered set of overlapping DNA inserts was sequencd
by dideoxynucletide chain termination method. 1836 nucleotide
sequences of the inserts of both pJM3 and pJM4 were determined
. A 303 bp of pJM4 edcodes a 11 kDa prolamin. This gene was
named RP3.The PR3 gene contains a single open reading frame
encoding 101 amino acids , 1046 bp of 5'' flanking reagion, and
487 bp of 3'' flanking reagion:No intron are present. Rice
prolamin cDNA are divided into three classes , namely classes I,
II,IIIbased on the nucleotide sequence homology of the coding
sequences. RP3 showed high homology with classes I cDNAs,pX24
and pS23,but low homology with class III cDNA, pS18.
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