Identification of serine residues in the connexin43 carboxyl tail important for BCR-mediated spreading of B-lymphocytes
| Autor: | May Dang-Lawson, Linda Matsuuchi, Kate Choi, Paul D. Lampe, Farnaz Pournia, Victor Mo |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
0303 health sciences
B-Lymphocytes breakpoint cluster region Actin remodeling Receptors Antigen B-Cell Cell Biology Biology Fusion protein Actins Cell biology Serine 03 medical and health sciences Transmembrane domain 0302 clinical medicine medicine.anatomical_structure hemic and lymphatic diseases Connexin 43 medicine Phosphorylation 030217 neurology & neurosurgery B cell Actin 030304 developmental biology |
| Zdroj: | Journal of cell science. 133(5) |
| ISSN: | 1477-9137 |
| Popis: | B-lymphocytes recognize antigen via B-cell antigen receptors (BCRs). This binding induces signaling, leading to B-cell activation, proliferation and differentiation. Early events of BCR signaling include reorganization of actin and membrane spreading, which facilitates increased antigen gathering. We have previously shown that the gap junction protein connexin43 (Cx43; also known as GJA1) is phosphorylated upon BCR signaling, and its carboxyl tail (CT) is important for BCR-mediated spreading. Here, specific serine residues in the Cx43 CT that are phosphorylated following BCR stimulation were identified. A chimeric protein containing the extracellular and transmembrane domains of CD8 fused to the Cx43 CT was sufficient to support cell spreading. Cx43 CT truncations showed that the region between amino acids 246-307 is necessary for B-cell spreading. Site-specific serine-to-alanine mutations (S255A, S262A, S279A and S282A) resulted in differential effects on both BCR signaling and BCR-mediated spreading. These serine residues can serve as potential binding sites for actin remodeling mediators and/or BCR signaling effectors; therefore, our results may reflect unique roles for each of these serines in terms of linking the Cx43 CT to actin remodeling. |
| Databáze: | OpenAIRE |
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