小非編碼RNA既見于微生物細胞,，也見于真核細胞。大多數(shù)已知微生物小RNA的功能是,，調(diào)控核心生理過程中所涉及的基因,，但我們關(guān)于小RNA的知識一直僅限于在實驗室中所培養(yǎng)的微生物。
“環(huán)境轉(zhuǎn)錄組學(xué)”（Metatranscriptomics）是最近發(fā)展起來的一種技術(shù)，可讓研究人員對未培養(yǎng)的微生物群落的集體轉(zhuǎn)錄組進行分析,。該方法能把人們對于轉(zhuǎn)錄組的認識拓展到其他更為奇異的微生物,。對從夏威夷以北名叫ALOHA的深水站不同深度處所取海水進行的一項新的“環(huán)境轉(zhuǎn)錄組學(xué)”分析，顯示了來自多樣化生物類群的一組數(shù)量巨大的小RNA新種類,。（生物谷Bioon.com）
生物谷推薦原始出處：
Nature 459, 266-269 (14 May 2009) | doi:10.1038/nature08055
Metatranscriptomics reveals unique microbial small RNAs in the ocean's water column
Yanmei Shi1, Gene W. Tyson1 & Edward F. DeLong1,2
1 Department of Civil and Environmental Engineering, and,
2 Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
Microbial gene expression in the environment has recently been assessed via pyrosequencing of total RNA extracted directly from natural microbial assemblages. Several such 'metatranscriptomic' studies1, 2 have reported that many complementary DNA sequences shared no significant homology with known peptide sequences, and so might represent transcripts from uncharacterized proteins. Here we report that a large fraction of cDNA sequences detected in microbial metatranscriptomic data sets are comprised of well-known small RNAs (sRNAs)3, as well as new groups of previously unrecognized putative sRNAs (psRNAs). These psRNAs mapped specifically to intergenic regions of microbial genomes recovered from similar habitats, displayed characteristic conserved secondary structures and were frequently flanked by genes that indicated potential regulatory functions. Depth-dependent variation of psRNAs generally reflected known depth distributions of broad taxonomic groups4, but fine-scale differences in the psRNAs within closely related populations indicated potential roles in niche adaptation. Genome-specific mapping of a subset of psRNAs derived from predominant planktonic species such as Pelagibacter revealed recently discovered as well as potentially new regulatory elements. Our analyses show that metatranscriptomic data sets can reveal new information about the diversity, taxonomic distribution and abundance of sRNAs in naturally occurring microbial communities, and indicate their involvement in environmentally relevant processes including carbon metabolism and nutrient acquisition.
