Two Conserved snoRNAs， SNORA50 and SNORA71， Demonstrated Divergent Tissue Expression Pattern Between Primates and Rodent Species

Abstract: The small nucleolar RNA (snoRNA) functions mainly as modulators of ribosomal RNA (rRNA). Growing evidence suggested that snoRNA may have broader functions than previously appreciated. Although the majority of known snoRNAs are conserved during vertebrate evolution， some of them have been documented to be species-specific. Significantly， we herein found that two conserved intron-encoded snoRNAs， SNORA50 and SNORA71， demonstrated species-specific tissue expression pattern， suggesting their functions in regulating individual organogenesis and phylogenesis. SNORA50， hosted by CCR4-NOT transcription complex， subunit 1 (Cnot1)， was ubiquitously expressed in various tissues of primate species (human and monkey) and bird (chicken). However， there was no detectable signal of SNORA50 in all 8 examined mouse tissues. SNORA71， hosted by small nucleolar RNA host gene 11 (snhg11)， was pervasively transcribed in the human and monkey tissues. Interestingly， SNORA71 was predominantly expressed in mouse brain as same as its host gene snhg11 did. SNORA71 was upregulated during mouse brain development. However， no obvious upregulation was observed during monkey brain develop ment from embryonic to adult stage， indicating that SNORA71 might have different functions in regulating neuron development of primates and mouse species. Collectively， we have identified a neurogenically highly expressed SNORA71 in mice， which provides important information to support snoRNA functions in regulating organogenesis during animal development. In addition， the species-specific transcriptional regulation of the conserved snoRNAs suggested their functional role in regulating individual development and phylogenesis.

CSTR: 32200.14.cjcb.2014.08.0009