{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nStudies of the UDP‐GlcNAc:lysosomal enzyme N‐acetylglucosamine‐1‐phosphotransferase have revealed that its catalytic (alpha/beta) subunits not only mediate the phosphorylation of a major subset of acid hydrolases but also directly recognize the protein determinants on these enzymes; furthermore, the gamma subunit is essential for the optimal phosphorylation of the remaining acid hydrolases and for promoting the addition of a second GlcNAc‐1‐phosphate moiety through its proposed mannose 6‐phosphate receptor homology domain."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn parallel, investigations into GNPTAB—one of the genes encoding a critical component of this enzyme—have demonstrated its key role in the sorting and proper intracellular targeting of lysosomal enzymes. Impaired GNPTAB function, as shown in human hair follicle models and corroborated by transgenic mouse studies, leads to defective melanosome sorting, reduced tyrosinase activity, and diminished hair follicle pigmentation, thereby identifying GNPTAB as an important regulator of pigmentary homeostasis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nAlthough neither abstract explicitly mentions MIR3118-4, integrating the findings suggests that if MIR3118-4 is part of this regulatory milieu, it could be implicated in modulating the expression or function of these key enzymatic players. Such regulation might affect both the mannose 6‐phosphate tagging of lysosomal acid hydrolases and the tailored control of melanosome biogenesis and tyrosinase trafficking in pigment cells. Therefore, MIR3118-4 may serve as a post‐transcriptional regulator that fine-tunes the activity of the phosphotransferase complex and its downstream effects on lysosomal enzyme sorting and hair pigmentation."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": "\n"}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Yi Qian, Intaek Lee, Wang-Sik Lee, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Functions of the alpha, beta, and gamma subunits of UDP-GlcNAc:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "J Biol Chem (2010)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1074/jbc.M109.068650"}], "href": "https://doi.org/10.1074/jbc.M109.068650"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "19955174"}], "href": "https://pubmed.ncbi.nlm.nih.gov/19955174"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Stephan Tiede, Jennifer E Hundt, Ralf Paus "}, {"type": "b", "children": [{"type": "t", "text": "UDP-GlcNAc-1-Phosphotransferase Is a Clinically Important Regulator of Human and Mouse Hair Pigmentation."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "J Invest Dermatol (2021)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.jid.2021.04.028"}], "href": "https://doi.org/10.1016/j.jid.2021.04.028"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "34116066"}], "href": "https://pubmed.ncbi.nlm.nih.gov/34116066"}]}]}]}