Evolution, Expression, and Possible Function of a Master Gene for Amplification of an Interspersed Repeated DNA Family in Rodents

Abstract

Publisher Summary BC1 RNA was originally identified as a small cytoplasmic RNA species, found primarily within the brain of rats that hybridized with a major—short interspersed repetitive element (SINE)— family of repetitive DNA sequences in the rat genome. A number of proposals have been made concerning the relationship of this single BC1 locus and other dispersed ID elements, both in terms of functional models and evolutionary relationships. Although no specific function has been demonstrated for either the BC1 RNA or ID elements, a number of lines of investigation suggest that the BC1 RNA gene plays some functional role, probably within neurons, throughout the rodent order. The BC1 RNA gene has also been shown to be a master gene for ID repeat amplification and evolution. The BC1 RNA gene is responsible for a large portion of the amplification of ID repeats via retroposition. There are two important aspects of the conservation of the BC1 RNA gene. The first is the conservation of transfer RNA-like features within the BC1 RNA gene. The second is the evidence that conservation provides regarding regions that may be under functional selection.