TY - JOUR

T1 - Discovery by proteogenomics and characterization of an RF-amide neuropeptide from cone snail venom

AU - Robinson, Samuel D

AU - Safavi-Hemami, Helena

AU - Raghuraman, Shrinivasan

AU - Imperial, Julita S

AU - Papenfuss, Anthony T

AU - Teichert, Russell W

AU - Purcell, Anthony W

AU - Olivera, Baldomero M

AU - Norton, Raymond S

PY - 2015

Y1 - 2015

N2 - UNLABELLED: In this study, a proteogenomic annotation strategy was used to identify a novel bioactive peptide from the venom of the predatory marine snail Conus victoriae. The peptide, conorfamide-Vc1 (CNF-Vc1), defines a new gene family. The encoded mature peptide was unusual for conotoxins in that it was cysteine-free and, despite low overall sequence similarity, contained two short motifs common to known neuropeptides/hormones. One of these was the C-terminal RF-amide motif, commonly observed in neuropeptides from a range of organisms, including humans. The mature venom peptide was synthesized and characterized structurally and functionally. The peptide was bioactive upon injection into mice, and calcium imaging of mouse dorsal root ganglion (DRG) cells revealed that the peptide elicits an increase in intracellular calcium levels in a subset of DRG neurons. Unusually for most Conus venom peptides, it also elicited an increase in intracellular calcium levels in a subset of non-neuronal cells.BIOLOGICAL SIGNIFICANCE: Our findings illustrate the utility of proteogenomics for the discovery of novel, functionally relevant genes and their products. CNF-Vc1 should be useful for understanding the physiological role of RF-amide peptides in the molluscan and mammalian nervous systems.

AB - UNLABELLED: In this study, a proteogenomic annotation strategy was used to identify a novel bioactive peptide from the venom of the predatory marine snail Conus victoriae. The peptide, conorfamide-Vc1 (CNF-Vc1), defines a new gene family. The encoded mature peptide was unusual for conotoxins in that it was cysteine-free and, despite low overall sequence similarity, contained two short motifs common to known neuropeptides/hormones. One of these was the C-terminal RF-amide motif, commonly observed in neuropeptides from a range of organisms, including humans. The mature venom peptide was synthesized and characterized structurally and functionally. The peptide was bioactive upon injection into mice, and calcium imaging of mouse dorsal root ganglion (DRG) cells revealed that the peptide elicits an increase in intracellular calcium levels in a subset of DRG neurons. Unusually for most Conus venom peptides, it also elicited an increase in intracellular calcium levels in a subset of non-neuronal cells.BIOLOGICAL SIGNIFICANCE: Our findings illustrate the utility of proteogenomics for the discovery of novel, functionally relevant genes and their products. CNF-Vc1 should be useful for understanding the physiological role of RF-amide peptides in the molluscan and mammalian nervous systems.

KW - Amino Acid Sequence

KW - Animals

KW - Cells, Cultured

KW - Conotoxins/genetics

KW - Conus Snail/chemistry

KW - Genetic Association Studies/methods

KW - Genomics

KW - Mice

KW - Mice, Inbred C57BL

KW - Molecular Sequence Data

KW - Mollusk Venoms/genetics

KW - Neurons/cytology

KW - Neuropeptides/genetics

KW - Proteomics

U2 - 10.1016/j.jprot.2014.11.003

DO - 10.1016/j.jprot.2014.11.003

M3 - Journal article

C2 - 25464369

VL - 114

SP - 38

EP - 47

JO - Journal of Proteomics

JF - Journal of Proteomics

SN - 1874-3919

ER -