[Construction of a cDNA library from liver tissue of rhesus monkey, Macaca mulatta].

Objective To screen the target rhesus genes and give some basic genetic evidences to its value as one of the most important animal model in biomedical study, we constructed a cDNA expression library from liver tissue of a healthy rhesus monkey. Methods With Trizol reagent, the total RNA was extracted from healthy rhesus liver tissue. By mutant Moloney Murine Leukemia Virus Reverse Transcriptase (MMLV-RT), the first-strand cDNA was synthesized from purified mRNA, and subsequently the second-strand cDNA was generated via E.coli DNA polymerase Ⅰ. Then, the EcoRⅠ adapter was added to the synthesized double-strand cDNA, which was subsequently digested by XhoⅠ restriction enzyme and fractionated with CHROMA APIN-400 column. The fractionated cDNA fragments to be longer than 0.5 kb were ligated into λ ZAP express vector to form the phagemid cDNA recombinants, which were further packaged into the λ ZAP cDNA library according to the standard protocol with phage λ Gold packaging extract. In order to get more stable clones with larger quantity, the primary library was amplified through infecting the host strain XL1-Blue MRF’. Then, the library titre, recombinant rate and length of inserted cDNA were measured, respectively. Results The capacity of the primary or unamplified library was 1.2×106 pfu. The titers of the unamplified library or the amplified library was 1.1×106 pfu/mL or 7.7×109 pfu/mL respectively, the percentages of recombinants were 99.3% and 98.2%,and the average lengths of the inserts were 2.0 kb and 2.3 kb, respectively. Conclusion An excellent cDNA expression library has been constructed successfully, which would lay solid foundation for transplantation study and pre-clinic evaluation of related drugs.