The small non-coding RNA Vaultrc5 is dispensable to mouse development

Area of Science:

• Molecular Biology
• RNA Biology
• Mammalian Physiology

Background:

• Vault RNAs (vRNAs) are conserved small non-coding RNAs transcribed by RNA polymerase III.
• vRNAs are components of vault particles and function as noncanonical miRNA precursors and riboregulators of autophagy.
• Known roles include regulation of cell proliferation, survival, viral response, drug resistance, and development, but mammalian physiology impact is unexplored.

Purpose of the Study:

• To investigate the in vivo physiological requirements of vault RNAs (vRNAs) in mammals.
• To characterize the function of Vault RNA component 5 (Vaultrc5), the sole murine vRNA, using a conditional loss-of-function mouse model.

Main Methods:

• Generation of a mouse line with a conditional Vaultrc5 loss-of-function allele.
• Analysis of mice constitutively null for Vaultrc5.

Main Results:

• Mice lacking Vaultrc5 are viable and histologically normal.
• A slight reduction in platelet counts was observed in null mice, suggesting a role for vRNAs in hematopoiesis.

Conclusions:

• Vault RNAs are not essential for murine viability but may play a role in regulating hematopoiesis, specifically platelet production.
• This study provides a foundation for further in vivo investigation of vRNA functions in various physiological and stress conditions.