Publications
Citation
Benyamin B, Maihofer AX, Schork AJ, Hamilton BA, Rao F, Schmid-SchÖnbein GW, Zhang K, Mahata M, Stridsberg M, Schork NJ, Biswas N, Hook VY, Wei Z, Montgomery GW, Martin NG, Nievergelt CM, Whitfield JB, O'Connor DT
Identification of Novel Loci Affecting Circulating Chromogranins and Related Peptides.
Human Molecular Genetics. 2016 Dec 22;
Abstract
Chromogranins are pro-hormone secretory proteins released from neuroendocrine cells, with effects on control of blood pressure. We conducted a genome-wide association study for plasma catestatin, the catecholamine release inhibitory peptide derived from chromogranin A (CHGA), and other CHGA- or chromogranin B (CHGB)-related peptides, in 545 US and 1252 Australian subjects. This identified loci on chromosomes 4q35 and 5q34 affecting catestatin concentration (P = 3.40 × 10(-30) for rs4253311 and 1.85 × 10(-19) for rs2731672, respectively). Genes in these regions include the proteolytic enzymes kallikrein (KLKB1) and Factor XII (F12). In chromaffin cells, CHGA and KLKB1 proteins co-localized in catecholamine storage granules. In vitro, kallikrein cleaved recombinant human CHGA to catestatin, verified by mass spectrometry. The peptide identified from this digestion (CHGA360-373) selectively inhibited nicotinic cholinergic stimulated catecholamine release from chromaffin cells. A proteolytic cascade involving kallikrein and Factor XII cleaves chromogranins to active compounds both in vivo and in vitro.