Construction of sesbania rostrata genomic library and molecular cloning of leghemoglobin genes

Liu, Y.; Fan, Y.

Scientia Agricultura Sinica 24(5): 77-82


ISSN/ISBN: 0578-1752
Accession: 007154909

Download citation:  

Article/Abstract emailed within 1 workday
Payments are secure & encrypted
Powered by Stripe
Powered by PayPal

The annual tropical legume Sesbania rostrata is characterized by nodulation not only on the roots but also along the stem. The stem nodules caused by specific fast-growing Rhizobium exhibit a very high capacity for nitrogen fixation. The oxygen-binding protein leghemoglobin plays an essential role in the development of symbiotic nitrogen-fixing function. The cosmid genomic library of S. rostrata was constructed, using a plant cosmid vector pEND 4K which consists of a mini-Ti plasmid of Agrobacterium tumefaciens and cos site of .LAMBDA. phage. Sizes of plant DNA insertion in clones were 25-33 Kbs. The restriction mapping shows that different recombinant contains various type of plant DNA insertion. The library was screened by in situ colony hybridization using the actively labelled leghemoglobin structural gene of Glycine max as a probe. Out of 1.0 .times. 105 recombinants, 4 clones containing leghemoglobin sequence were obtained. Homology between leghemoglobin genes of G. max and S. rostrata was confirmed by southern blot hybridization. The differences of hybridization strength may suggest that clones contain different genes of leghemoglobin gene family.