To disclose the structural and functional relationships between MLC1 and Cx43 in astrocytes and the possible effects of MLC1 pathological mutations on them, we first generated U251 astrocytoma cells stably producing recombinant MLC1 wild type (WT) or MLC1 carrying two mutations found in MLC patients: c.178-10 t>a (Pt1) and c.177+1 g>t (Pt2) [31,32]. The gene discussed is MLC1; the disease is astrocytoma (excluding glioblastoma).