{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nDUSP13B, also known as TMDP, is a testis‐specific dual‐specificity phosphatase encoded by the DUSP13 gene that plays a unique role in modulating stress‐activated mitogen‐activated protein kinase (MAPK) signaling. In testicular cells—specifically in spermatocytes and round spermatids—DUSP13B preferentially attenuates the activation of JNK and p38 (with a lesser effect on ERK), thereby diminishing AP‑1–dependent transcription. This suggests that DUSP13B may serve as a protective regulator during spermatogenesis by controlling excessive stress‐induced signaling."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nAdditional insights from studies on the broader DUSP13 gene products indicate that DUSP13B/TMDP and its muscle‐restricted counterpart (DUSP13A/MDSP) arise from a single gene by alternative open reading frames. Structural analyses of TMDP reveal distinct substrate recognition motifs and active site features compared with other dual‐specificity phosphatases, which likely underpin its substrate preferences and selective regulatory functions observed postnatally. The conserved and developmentally upregulated expression profile of DUSP13B further underscores its physiological significance in mature testicular tissues."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": ""}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Chiaki Katagiri, Kouhei Masuda, Miyuki Nomura, et al. "}, {"type": "b", "children": [{"type": "t", "text": "DUSP13B/TMDP inhibits stress-activated MAPKs and suppresses AP-1-dependent gene expression."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Mol Cell Biochem (2011)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1007/s11010-011-0749-x"}], "href": "https://doi.org/10.1007/s11010-011-0749-x"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "21360282"}], "href": "https://pubmed.ncbi.nlm.nih.gov/21360282"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Hsu-Hsin Chen, Ralf Luche, Bo Wei, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Characterization of two distinct dual specificity phosphatases encoded in alternative open reading frames of a single gene located on human chromosome 10q22.2."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "J Biol Chem (2004)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1074/jbc.M405286200"}], "href": "https://doi.org/10.1074/jbc.M405286200"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "15252030"}], "href": "https://pubmed.ncbi.nlm.nih.gov/15252030"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Seung Jun Kim, Dae-Gwin Jeong, Tae-Sung Yoon, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Crystal structure of human TMDP, a testis-specific dual specificity protein phosphatase: implications for substrate specificity."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Proteins (2007)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1002/prot.21197"}], "href": "https://doi.org/10.1002/prot.21197"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "17044055"}], "href": "https://pubmed.ncbi.nlm.nih.gov/17044055"}]}]}]}