Identification of proteins immunologically related to vertebrate lamins in the nuclear matrix of the myxomycete Physarum polycephalum.

Lamin-like proteins have been identified as components of the nuclear matrix of the myxomycete Physarum polycephalum. A 67 kDa homologue was detected by immunoblotting of nuclear matrix proteins with affinity-purified anti-lamin antibodies of human autoimmune sera. A 65 kDa lamin B homologue was identified with polyclonal antibodies against turkey erythrocyte lamin B in nuclei and nuclear matrix of Physarum amoebae and plasmodia. Indirect immunofluorescence microscopy revealed that the 65 and 67 kDa proteins are localized in the nuclear lamina of plasmodial nuclei.