Transcriptome analysis of three cultivars of Poria cocos reveals genes related to the biosynthesis of polysaccharides

Poria cocos (P. cocos) polysaccharides (PCPs) are used to improve immunity and possess antitumor activities. We compared three cultivars of P. cocos (5.78, XJ 28 and JHYH) PCP contents. Then we determined that malZ, galA, SORD, gnl and bglX are key enzymes within the PCP biosynthetic pathway by using HiSeq2500 transcriptome and qRT-PCR validation. Our results provide more detailed information about the PCP biosynthesis pathway at the molecular level in P. cocos and establish the functions for the molecular breeding to produce polysaccharides in general for therapeutic use in Chinese medicinal plants.