Model depicting Cx43-Hapln1a mediated effect on skeletal patterning during fin regeneration.

<p>(A) Proposed pathway for Hapln1a mediated effects of Cx43. Hapln1a functions in a <i>cx43</i>-dependent, but <i>sema3d</i>-independent pathway, positively influencing cell proliferation and inhibiting joint formation. (B) Cartoon illustrating the compartments of gene in the regenerating fin: The <i>cx43</i> mRNA is expressed throughout the mesenchyme (red) accompanied by <i>cx43</i>-dependent <i>hapln1a</i> upregulation in the same compartment (red), but primarily in the distal blastema (blue-red) and to a lesser extent in the proximal skeletal precursor cells (blue). e, epithelium; m, mesenchyme; b, blastema; db, distal blastema; spc, skeletal precursor cells; ble, basal layer of epidermis.