BioChem - DOS

Improved production of heterologous lipase in Trichoderma reesei by RNAi mediated gene silencing of an endogenic highly expressed gene

Bioresource technology : biomass, bioenergy, biowastes, conversion technologies, biotransformations, production technologies

Qin, Li-Na; Cai, Fu-Rong; Dong, Xin-Rui; Huang, Zhen-Bang; Tao, Yong; Huang, Jian-Zhong; Dong, Zhi-Yang

<P><B>Highlights</B></P><P>&#x025BA; An <I>Aspergillus niger</I> lipase gene was successfully expressed in the <I>Trichoderma reesei</I>. &#x025BA; Expression of cellobiohydrolase was suppressed via RNAi method. &#x025BA; Different insertion sites in the genome caused different silencing levels. &#x025BA; Strains with reduced CBH1 exhibited 1.8&ndash;3.2 fold increase in lipase production.</P> <P><B>Abstract</B></P><P>A lipase gene (Lip) of the <I>Aspergillus niger</I> was <I>de novo</I> synthesized and expressed in the <I>Trichoderma reesei</I> under the promoter of the cellobiohydrolase I gene (<I>cbh1</I>). RNAi-mediated gene silencing was successfully used to further improve the recombinant lipase production via down-regulation of CBHI which comprised more than 60% of the total extracellular proteins in <I>T. reesei</I>. The gene and protein expression of CBHI and recombinant lipase were analyzed by real-time PCR, SDS&ndash;PAGE and activity assay. The results demonstrated that RNAi-mediated gene silencing could effectively suppress <I>cbh1</I> gene expression and the reduction of CBHI could result in obvious improvement of heterologous lipase production. The reconstructed strains with decreased CBHI production exhibited 1.8- to 3.2-fold increase in lipase activity than that of parental strain. The study herein provided a feasible and advantageous method of increasing heterologous target gene expression in <I>T. reesei</I> through preventing the high expression of a specific endogenenous gene by RNA interference.</P>

2012

0960-8524

109

pp.116-122

10.1016/j.biortech.2012.01.013

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART58595346

Lipase; Trichoderma reesei; RNAi; Cellobiohydrolase I; Heterologous expression