.beta.-NGF-endopeptidase: structure and activity of a kallikrein encoded by the gene mGK-22

Abstract

Mouse nerve growth factor (NGF) is cleaved at a histidine-methionine bond to release an NH2-terminal octapeptide (NGF1-8). The enzyme responsible, beta-NGF-endopeptidase, is structurally and functionally similar to gamma-NGF and epidermal growth factor-binding protein (EGF-BP) and cleaves mouse low molecular weight kininogen to produce bradykinin-like activity. These data have suggested that, like gamma-NGF and EGF-BP, beta-NGF-endopeptidase is a mouse glandular kallikrein. Evidence for a physiological role for NGF1-8 encouraged studies to further characterize the structure and function of this enzyme. Purified beta-NGF-endopeptidase migrated as a single band on isoelectric focusing and reducing SDS-polyacrylamide gels. As was expected, it removed NGF1-8 from NGF. Interestingly, enzymatic activity on an artificial substrate, and on NGF, was inhibited by NGF1-8 and by bradykinin. These studies further supported the view that beta-NGF-endopeptidase acts on both NGF and kininogen. The first 30 NH2-terminal amino acids of beta-NGF-endopeptidase were sequenced. This analysis demonstrated that the enzyme is encoded by the gene designated mGK-22 (Evans et al., 1987). The sequence of this gene corresponds to that of EGF-BP type A (Anundi et al., 1982; Drinkwater et al., 1987), and so studies were performed to determine whether or not beta-NGF-endopeptidase participates in EGF complex formation. Chromatographic and kinetic data gave no evidence that beta-NGF-endopeptidase is an EGF-binding protein. Our studies suggest that contamination of high molecular weight (HMW) EGF preparations with beta-NGF-endopeptidase erroneously led to earlier designation of the product of mGK-22 as an EGF-BP.(ABSTRACT TRUNCATED AT 250 WORDS)

Prohormone Convertases in Mouse Submandibular Gland: Co-localization of Furin and Nerve Growth Factor

“…Furthermore, the ␣-and ␥-subunits have not been detected in other NGF-producing cells and tissues (Murphy et al 1986;Pantazis 1983). A second endopeptidase has been identified that removes the amino terminal octapeptide of mature NGF, but it does not act at the cleavage site necessary for processing mature NGF from its precursor (Fahnestock et al 1991).…”

An overview of the kallikrein gene families in humans and other species: emerging candidate tumour markers

“…Similar to the human family, only one mouse kallikrein (mKLK1 or mGK6) has true kininogenase activity [13]. Other mouse kallikrein proteins have different types of activities; mGK3 and mGK4 being nerve growth factor binding and processing enzymes and mGK9, mGK13 and mGK22 being epidermal growth factor-binding proteins; mGK22 is a nerve growth factor-inactivating enzyme; mGK16 is ␥-renin and mGK26 is prorenin-converting enzyme-2 [16,17]. With the expansion of the mouse family of kallikreins, it is becoming necessary to develop a revised nomenclature of mouse kallikreins, that takes into consideration the newly cloned genes, their map location and phylogenetic relatedness to their human orthologues.…”

The testosterone-dependent and independent transcriptional networks in the hypothalamus of Gpr54 and Kiss1 knockout male mice are not fully equivalent

“…Klk1b22 , also known as β-nerve growth factor (NGF)-endopeptidase [36] is a member of the kallikrein gene cluster that has been expanded by tandem gene duplication. The predicted activity pattern for Klk1b22 is cleavage at Arg-Ser residues, an arrangement found within mouse pre-pro kisspeptin that would result in a 52 amino acid peptide, similar to the Kp54 seen in humans.…”