Wilaiwan Chotigeat, Sarapee Duangchu, and Amornrat Phongdara

pp. 555 - 559

Abstract

Latex from Hevea brasiliensis contains 30-50% (w/w) of natural rubber (cis-1,4-polyisoprene), the important raw
material for many rubber industries. We have constructed a cDNA library from the latex of H. brasiliensis to investigate the
expressed genes and molecular events in the latex. We analyzed 412 expressed sequence tags (ESTs). More than 90% of the
EST clones showed homology to previously described sequences in public databases. Functional classification of the ESTs
showed that the largest category were proteins of unknown function (30.1%), 11.4% of ESTs encoded for rubber synthesisrelated proteins (RS) and 8.5% for defense or stress related proteins (DS). Those with no significant homology to known
sequences (NSH) accounted for 8.7%, primary metabolism (PM) and gene expression and RNA metabolism were 7.8% and
6.6%, respectively. Other categories included, protein synthesis-related proteins (6.6%), chromatin and DNA metabolism
(CDM 3.9%), energy metabolism (EM 3.4%), cellular transport (CT 3.2%), cell structure (CS 3.2%), signal transduction (ST
2.2%), secondary metabolism (SM 1.7%), protein fate (PF 2.2%), and reproductive proteins (RP 0.7%).