دورية أكاديمية
Structure of the lens MP20 mediated adhesive junction.
العنوان: | Structure of the lens MP20 mediated adhesive junction. |
---|---|
المؤلفون: | Nicolas WJ; Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095.; Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095., Shiriaeva A; Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095., Martynowycz MW; Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095., Grey AC; Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, NZ., Ruma Y; Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095.; Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095., Donaldson PJ; Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, NZ., Gonen T; Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095.; Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095.; Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095. |
المصدر: | BioRxiv : the preprint server for biology [bioRxiv] 2024 May 13. Date of Electronic Publication: 2024 May 13. |
نوع المنشور: | Journal Article; Preprint |
اللغة: | English |
بيانات الدورية: | Country of Publication: United States NLM ID: 101680187 Publication Model: Electronic Cited Medium: Internet NLM ISO Abbreviation: bioRxiv Subsets: PubMed not MEDLINE |
مستخلص: | Human lens fiber membrane intrinsic protein MP20 is the second most abundant membrane protein of the human eye lens. Despite decades of effort its structure and function remained elusive. Here, we determined the MicroED structure of full-length human MP20 in lipidic-cubic phase to a resolution of 3.5 Å. MP20 forms tetramers each of which contain 4 transmembrane α-helices that are packed against one another forming a helical bundle. Both the N- and C- termini of MP20 are cytoplasmic. We found that each MP20 tetramer formed adhesive interactions with an opposing tetramer in a head-to-head fashion. These interactions were mediated by the extracellular loops of the protein. The dimensions of the MP20 adhesive junctions are consistent with the 11 nm thin lens junctions. Investigation of MP20 localization in human lenses indicated that in young fiber cells MP20 was stored intracellularly in vesicles and upon fiber cell maturation MP20 inserted into the plasma membrane and restricted the extracellular space. Together these results suggest that MP20 forms lens thin junctions in vivo confirming its role as a structural protein in the human eye lens, essential for its optical transparency. |
معلومات مُعتمدة: | P41 GM136508 United States GM NIGMS NIH HHS |
فهرسة مساهمة: | Keywords: Lens membrane protein; MicroED; cryoEM; ion-beam milling; junction; lipidic cubic phase |
تواريخ الأحداث: | Date Created: 20240527 Latest Revision: 20240610 |
رمز التحديث: | 20240610 |
مُعرف محوري في PubMed: | PMC11118347 |
DOI: | 10.1101/2024.05.13.594022 |
PMID: | 38798449 |
قاعدة البيانات: | MEDLINE |
DOI: | 10.1101/2024.05.13.594022 |
---|