title: Identification and characterization of microRNAs in pearl oyster Pinctada martensii by Solexa deep sequencing.
abstract: MicroRNAs (miRNAs) are short-nucleotide RNA molecules that function as negative regulators of gene expression in various organisms. However, miRNAs of Pinctada martensii have not been reported yet. P. martensii is one of the main species cultured for marine pearl production in China and Japan. In order to obtain the repertoire of miRNAs in P. martensii, we constructed and sequenced small RNA libraries prepared from P. martensii by Solexa deep sequencing technology and got a total of 27,479,838 reads representing 3,176,630 distinct sequences. After removing tRNAs, rRNAs, snRNAs, and snoRNAs, 10,596,306 miRNA reads representing 18,050 distinct miRNA reads were obtained. Based on sequence similarity and hairpin structure prediction, 258 P. martensii miRNAs (pm-miRNA) were identified. Among these pm-miRNAs, 205 were conserved across the species, whereas 53 were specific for P. martensii. The 3' end sequence of U6 snRNA was obtained from P. martensii by 3' rapid amplification of cDNA end PCR reaction and sequence-directed cloning. Eight conserved pm-miRNAs and two novel pm-miRNAs were validated by stem-loop quantitative real-time PCR with U6 snRNA as an internal reference gene. pm-miRNAs and the reported biomineralization-related genes were subjected to target analysis by using target prediction tools. Some of the pm-miRNAs, such as miR-2305 and miR-0046, were predicted to participate in biomineralization by regulating the biomineralization-related genes. Thus, this study demonstrated a large-scale characterization of pm-miRNAs and their potential function in biomineralization, providing a foundation to understand shell formation.
authors.affiliation: Fishery College, Guangdong Ocean University, 40 East Jiefang Road, Xiashan District, Zhanjiang City, Guangdong, 524025, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Jiao
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zheng
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Du
authors.forename: Qingheng
authors.initials: Q
authors.lastname: Wang
authors.forename: Ronglian
authors.initials: R
authors.lastname: Huang
authors.forename: Yuewen
authors.initials: Y
authors.lastname: Deng
authors.forename: Shangli
authors.initials: S
authors.lastname: Shi
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D017124:Conserved Sequence / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D015723:Gene Library; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods; D035683:MicroRNAs / Q000235:genetics*; D049911:Pinctada / Q000235:genetics*; D012342:RNA, Small Nuclear / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity
chemical_list: D017931:DNA Primers; D035683:MicroRNAs; D012342:RNA, Small Nuclear