{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nRecent studies have revealed that the protein originally characterized as CHAP (Cytoskeletal Heart-enriched Actin-associated Protein) functions as a critical component of the Z-disc in striated muscle. It is dynamically localized both to the sarcomere, where it associates with filamentous actin and interacts with α‐actinin, and to the nucleus, suggesting a dual role in structural organization and gene regulation. Knockdown experiments in zebrafish have demonstrated that disruption of this protein impairs proper cardiac and skeletal muscle development."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nFurther characterization of CHAP in chick and mouse models confirms its developmentally regulated expression in heart and skeletal muscle, as well as in smooth muscle cells of major arteries in adults. The presence of a PDZ domain and a nuclear localization signal indicates that CHAP may integrate signaling cues with cytoskeletal dynamics, ensuring the integrity and function of the contractile apparatus throughout muscle maturation and homeostasis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn addition to CHAP, studies on related Z-disc-associated proteins such as SYNPO2L have highlighted a cooperative mechanism in muscle cells, where SYNPO2L interacts with α‐actinin and facilitates actin bundle formation. This synergy is essential for the proper assembly and maintenance of sarcomeric structures, further emphasizing the importance of Z-disc complexes in controlling both the mechanical stability and signaling functions that underlie muscle development and function."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": "\n"}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Abdelaziz Beqqali, Jantine Monshouwer-Kloots, Rui Monteiro, et al. "}, {"type": "b", "children": [{"type": "t", "text": "CHAP is a newly identified Z-disc protein essential for heart and skeletal muscle function."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "J Cell Sci (2010)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1242/jcs.063859"}], "href": "https://doi.org/10.1242/jcs.063859"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "20215401"}], "href": "https://pubmed.ncbi.nlm.nih.gov/20215401"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Willemijn van Eldik, Abdelaziz Beqqali, Jantine Monshouwer-Kloots, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Cytoskeletal heart-enriched actin-associated protein (CHAP) is expressed in striated and smooth muscle cells in chick and mouse during embryonic and adult stages."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Int J Dev Biol (2011)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1387/ijdb.103207wv"}], "href": "https://doi.org/10.1387/ijdb.103207wv"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "21948713"}], "href": "https://pubmed.ncbi.nlm.nih.gov/21948713"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Hiroshi Yamada, Hirona Osaka, Nanami Tatsumi, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Direct Binding of Synaptopodin 2-Like Protein to Alpha-Actinin Contributes to Actin Bundle Formation in Cardiomyocytes."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Cells (2024)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.3390/cells13161373"}], "href": "https://doi.org/10.3390/cells13161373"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "39195263"}], "href": "https://pubmed.ncbi.nlm.nih.gov/39195263"}]}]}]}