{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nAlthough none of the provided abstracts directly describe RSBN1L, a synthesis of the studies on proteins with related functions suggests that RSBN1L may participate in cellular processes that involve the regulation of actin dynamics and extracellular signal‐regulated kinase (ERK) signaling. For instance, one study showed that under hypoxic conditions—such as in pulmonary arterial hypertension (PAH)—an upregulated enzyme, MICAL2, enhances the proliferation of pulmonary arterial smooth muscle cells by activating ERK1/2 signaling, while a microRNA (miR‑205‑5p) counteracts this effect by targeting MICAL2."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": " \n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nAnother investigation into the enzymology of MICAL2 demonstrated that this flavin‐dependent monooxygenase, which preferentially utilizes NADPH for the reduction of its flavin cofactor, catalyzes the oxidation of a methionine residue within actin. This redox regulation of actin permits the controlled disassembly of actin filaments—a function that minimizes wasteful cofactor consumption and the deleterious production of hydrogen peroxide."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": " \n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nAdditional work has highlighted the importance of MICAL2 in muscle biology. Increased levels of MICAL2 during the myogenic differentiation of adult and pluripotent stem cells facilitate actin filament turnover, thus contributing to the proper formation and homeostasis of skeletal, smooth, and cardiac muscle fibers. In vivo disruption of MICAL2 leads to deficits in muscle actin organization and functionality, underscoring its essential role in tissue regeneration."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": " Moreover, its role extends to the differentiation of myofibroblasts, implicating MICAL2 in fibrotic conditions."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "4"}]}, {"type": "t", "text": " \n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nComplementing these insights into cytoskeletal regulation and ERK signaling, studies on EBITEIN1—a protein that binds ERK1/2—demonstrate that the modulation of ERK activity (both when phosphorylated and nonphosphorylated) is critical for cellular morphogenesis in spermatids. EBITEIN1 is itself phosphorylated by ERK2 and appears to participate in signaling events that control the transition of round spermatids into mature spermatozoa."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "5"}]}, {"type": "t", "text": " \n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nTogether, these studies outline a network in which redox-regulated actin modifications and ERK-dependent signaling cooperate to control cell proliferation, differentiation, and tissue homeostasis. While RSBN1L is not directly characterized in these reports, its putative designation as a “RSBN1‐like” protein invites speculation that it may participate in analogous regulatory mechanisms—possibly influencing actin dynamics and/or modulating ERK signaling—to impact processes such as vascular remodeling, muscular regeneration, or spermatid maturation.\n"}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Wei Tao, WeiMing Sun, HaiLong Zhu, et al. "}, {"type": "b", "children": [{"type": "t", "text": "miR-205-5p suppresses pulmonary vascular smooth muscle cell proliferation by targeting MICAL2-mediated Erk1/2 signaling."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Microvasc Res (2019)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.mvr.2019.03.001"}], "href": "https://doi.org/10.1016/j.mvr.2019.03.001"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "30853343"}], "href": "https://pubmed.ncbi.nlm.nih.gov/30853343"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Claudia A McDonald, Ying Yi Liu, Bruce A Palfey "}, {"type": "b", "children": [{"type": "t", "text": "Actin stimulates reduction of the MICAL-2 monooxygenase domain."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Biochemistry (2013)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1021/bi4008462"}], "href": "https://doi.org/10.1021/bi4008462"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "23927065"}], "href": "https://pubmed.ncbi.nlm.nih.gov/23927065"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Nefele Giarratana, Filippo Conti, Rita La Rovere, et al. "}, {"type": "b", "children": [{"type": "t", "text": "MICAL2 is essential for myogenic lineage commitment."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Cell Death Dis (2020)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1038/s41419-020-02886-z"}], "href": "https://doi.org/10.1038/s41419-020-02886-z"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "32811811"}], "href": "https://pubmed.ncbi.nlm.nih.gov/32811811"}]}, {"type": "r", "ref": 4, "children": [{"type": "t", "text": "Fan Jiang, Jiang Cao, Renyi Kong, et al. "}, {"type": "b", "children": [{"type": "t", "text": "MICAL2 regulates myofibroblasts differentiation in epidural fibrosis via SRF/MRTF-A signaling pathway."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Life Sci (2021)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.lfs.2021.119045"}], "href": "https://doi.org/10.1016/j.lfs.2021.119045"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "33453238"}], "href": "https://pubmed.ncbi.nlm.nih.gov/33453238"}]}, {"type": "r", "ref": 5, "children": [{"type": "t", "text": "Kenji Miura, Junko Imaki "}, {"type": "b", "children": [{"type": "t", "text": "Identification of ERK2-binding domain of EBITEIN1, a novel ERK2-binding protein."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Biochim Biophys Acta (2008)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.bbapap.2008.05.015"}], "href": "https://doi.org/10.1016/j.bbapap.2008.05.015"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "18590835"}], "href": "https://pubmed.ncbi.nlm.nih.gov/18590835"}]}, {"type": "r", "ref": 6, "children": [{"type": "t", "text": "Kenji Miura "}, {"type": "b", "children": [{"type": "t", "text": "ERK2-binding domain is required for phosphorylation of EBITEIN1, a potential downstream interactor of ERK2."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Biochem Biophys Res Commun (2008)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.bbrc.2008.08.005"}], "href": "https://doi.org/10.1016/j.bbrc.2008.08.005"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "18700133"}], "href": "https://pubmed.ncbi.nlm.nih.gov/18700133"}]}]}]}