In SilicoPrediction andIn VitroCharacterization of Multifunctional Human RNase3

Abstract

Human ribonucleases A (hRNaseA) superfamily consists of thirteen members with high-structure similarities but exhibits divergent physiological functions other than RNase activity. Evolution of hRNaseA superfamily has gained novel functions which may be preserved in a unique region or domain to account for additional molecular interactions. hRNase3 has multiple functions including ribonucleolytic, heparan sulfate (HS) binding, cellular binding, endocytic, lipid destabilization, cytotoxic, and antimicrobial activities. In this study, three putative multifunctional regions, 34RWRCK38 (HBR1), 75RSRFR79 (HBR2), and 101RPGRR105 (HBR3), of hRNase3 have been identified employing in silico sequence analysis and validated employing in vitro activity assays. A heparin binding peptide containing HBR1 is characterized to act as a key element associated with HS binding, cellular binding, and lipid binding activities. In this study, we provide novel insights to identify functional regions of hRNase3 that may have implications for all hRNaseA superfamily members.

Insights into the Antimicrobial Mechanism of Action of Human RNase6: Structural Determinants for Bacterial Cell Agglutination and Membrane Permeation

“…RNase2 acts as a potent modulator of the immune host system, and additionally displays a high antiviral activity against rhinovirus, adenovirus and syncytial respiratory virus in a RNase catalytic activity dependent manner [ 15 , 16 , 17 ]. RNase3 possesses a highly antimicrobial activity against bacteria [ 11 , 18 , 19 , 20 , 21 ], and many parasites, such as helminths and protozoa [ 22 ]. By contrast, the antimicrobial properties of RNase3 are not dependent on the ribonuclease activity of the protein [ 18 , 23 ].…”

Heparin-Promoted Cellular Uptake of the Cell-Penetrating Glycosaminoglycan Binding Peptide, GBPECP, Depends on a Single Tryptophan

“…We have recently identified a multifunctional CPP from human eosinophil cationic protein, ECP (also known as human ribonuclease 3, hRNase3). The peptide has substantial heparan sulfate (HS), heparin (HP), and lipid binding activities. , It also exhibits epithelial cell targeting, antimigration, anti-invasion, antiangiogenesis, and immunomodulatory activities. ECP interacts with cell surface glycosaminoglycans (GAGs), particularly HS.…”

Basic Amino Acid Residues of Human Eosinophil Derived Neurotoxin Essential for Glycosaminoglycan Binding

“…Putative HBRs on ECP including 34 RWRCK 38 , 73 RSRFR 77 , and 101 RPGRR 105 have been aligned with the corresponding segments of the other 12 RNases employing Clustal W2 [50]. Among these three HBRs, only HBR1 on ECP ( 34 RWRCK 38 ) is found in a position comparable with HBR1 on EDN ( 34 QRRCK 38 ) within a primary sequence that is 60% homologous.…”