Meprin A subunit beta (MEP1B)

Meprin A subunit beta (MEP1B) is a zinc-dependent membrane-bound metalloprotease that plays a critical role in extracellular protein processing and tissue remodeling[1][3][5]. It is a multidomain enzyme, predominantly expressed in the brush border of kidney and intestinal epithelial cells, and also found in leukocytes and certain cancer cells[1][5]. Meprin β selectively hydrolyzes a broad spectrum of substrates, including components of the extracellular matrix (procollagen I and III, tenascin-C), growth factors, adhesion molecules, cytokines (such as interleukin-6), and amyloid precursor protein (APP)[1][3][4]. Its proteolytic activity influences collagen fibril formation, cell–matrix interactions, and activation of key regulatory enzymes like ADAM10 through propeptide removal[1][4]. Unlike its homolog meprin alpha, meprin beta is largely membrane-bound, but can be shed from the cell surface by enzymes such as ADAM10 and ADAM17[4]. Dysregulation of meprin β is implicated in a variety of pathologies, including cancer, inflammatory bowel disease, and neurodegenerative disorders due to the generation of aggregation-prone amyloid-beta peptides following APP cleavage[3][4]. Meprin β's activity is controlled by posttranslational modifications, proteolytic activation, and interactions with tetraspanins (e.g., TSPAN8), which help organize it within specialized membrane microdomains[1]. The enzyme's broad substrate specificity presents challenges for therapeutic intervention, but also makes it a potential drug target and pathophysiological biomarker in several diseases[2][4].

Other names

Meprin βEndopeptidase-2Meprin BN-benzoyl-L-tyrosyl-P-amino-benzoic acid hydrolase subunit betaPABA peptide hydrolasePPH betameprin A subunit betaN-benzoyl-L-tyrosyl-P-amino-benzoic acid hydrolase beta subunit

Metalloprotease inhibition (blocking substrate cleavage and downstream effects); Interfering with membrane shedding (preventing release or activation of other proteins); Modulation of extracellular matrix metabolism