CLONING OF SPECIFIC GENE EXPRESSION CONTROL ELEMENTS FROM DUCKWEED SPIRODELA POLYRRHIZA DB2

Abstract

Cloning  and  utilization  of  specific  gene  expression  conttol  element  of  plants  in  order  to  increase  the expression ability of recombinant genes are vital research area in plant biotechnology. Research of Duckweeds, monocotyledonous  plants  with  a  high  content  of  proteins  and  polysaccharides,  is  a  new  initiative  in  our laboratory. We have carried out optimization  method  of DNA isolation. Good quality DNA was obtained by the isolation methods CTAB and PVP, CTAB and PEG, and SDS and PVP. A PCR amplification  of the total genomic  DNA  revealed,  the  full-length  Spirodela polyrrhiza  DB2 ubiquitin  expression  control  element,  the

promoter plus  5'UTR  and  intton,  was  2 kb  in  length, and the promoter  plus  5' UTR  section  1 kb.  The PCR products were cloned into pJET2.1, checked by restriction  enzymes and sequenced. The fiill-lengtb Spirodela polyrrhiza DB2 ubiquitin  expression  control  element,  the promoter plus  5'UTR  and  intton was  exactly 2013 bp, and the promoter plus 5' UTR region was  1033 bp. Compared with the sequence reported, there were  four substitation positions in the promoter region, and two in the intton region. Utilization of this isolated promoter and full-length  gene expression conttol element requires father  investigation.