The Construction of Full-Length cDNA Library for Otodectes cynotis

Background Otodectes cynotis (Hering, 1838) is the pathogen of otodectic mange distributed worldwide. The mite mainly infests carnivores and, sometimes, humans. However, due to the lack of cDNA library, research on its pathogenesis has been challenging. Methods To solve this problem, the present study first sampled O. cynotis mites from an infested cat from Xi’an, China, for RNA extraction. Then, the full-length cDNA library was constructed using the SMART technique. Finally, positive clones > 500 bp and Hsc70-5 gene fragment specifically amplified from the cDNA library were sequenced and analyzed to verify the library’s reliability. Results Results showed that RNA extracted from 300 mites had good quality with a concentration of 149 ng/μl and OD260/OD280 of 1.99. The library satisfied the quality standard of a good library with a titer of 5.02 × 10 5 PFU/ml and a combination rate of 97.61%. In addition, clone 4 and Hsc70-5 showed 98.38% and 99.72% identity with Ef1-α and Hsc70-5 gene sequences of O. cynotis in GenBank, respectively. Conclusion The cDNA library of O. cynotis constructed here was successful and reliable, creating the basis for research on RNA sequencing and functional genes of O. cynotis .