Duplication and functional diversification of pancreatic ribonuclease (RNASE1) gene

Abstract

Adaptation is one of the most fundamental issues in the studies of organismal evolution. Pancreatic ribonuclease is a very important digestive enzyme and secreted by the pancreas. Numerous studies have suggested that RNASE1 gene duplication is closely related to the functional adaptation of the digestive system in the intestinal fermentation herbivores. RNASE1 gene thus becomes one of the most important candidate genetic markers to study the molecular mechanism of adaptation of organisms to the feeding habit. Interestingly, RNASE1 gene duplication has also been found in some non-intestinal fermentation mammals, suggesting that RNASE1 gene may have produced novel tissue specificity or functions in these species. In this review, RNASE1 gene and its implications in adaptive evolution, especially in association with the feeding habit of organisms, are summarized. RNASE1 gene, digestive enzyme, gene duplication, adaptive evolution, intestinal fermentation, functional diversification Citation: Wang X Y, Li N Z, Yu L, et al. Duplication and functional diversification of pancreatic ribonuclease (RNASE1) gene.

Summary of phylogeny in subfamily Colobinae (Primate: Cercopithecidae)

“…Besides the features as described above, the subfamily Colobinae has evolved a complex ruminant-like stomach and foregut in which microbes ferment these indigestible plant materials [4], leading to their unique adaptation to the leaf-eating feeding habits [5][6][7][8]. In view of this, the Colobinae has also been the crucial model animals for the study of the molecular mechanisms of adaptive evolution [9,10].…”

“…In view of this, the Colobinae has also been the crucial model animals for the study of the molecular mechanisms of adaptive evolution [9,10]. The pancreatic ribonuclease gene (RNASE) duplication has been believed to be closely related to the adaptation of Colobines to the unique leaf-feeding lifestyle [5][6][7][8]. While all of the other primates have only one RNASE1 gene, multiple RNASE1 genes have been intriguingly observed in Colobines, evolving rapidly under positive selection for enhanced digestive efficiencies, as an adaptive response to the increased demands for the enzyme for digesting bacterial RNA (Figure 2).…”