Objective  By using yeast two-hybrid system

an interaction is proven existing between mutated SOD1 cDNA and segment of Homo sapiens MAP/MARK1. In the present study the interaction between the two proteins was further determined in human embryonic kidney cell 293 (HEK293) to verify the results of yeast two-hybrid system.   Methods  Mammalian expression vectors pCMV-Myc containing mutated SOD1 cDNA and pCMV-HA containing segments of Homo sapiens MAP/MARK1 were constructed by PCR and double enzyme digestion. They were transfected to HEK293 cells and examined by coimmunoprecipitation.   Results  The coimmunoprecipitation experiments showed when the recombinated plasmid pCMV-Myc with mutated SOD1 cDNA was cotransfected with plasmid pCMV-Myc or plasmid pCMV-HA

there was no binding protein observed in HEK293 cells. However

when the recombinated plasmid pCMVMyc with mutated SOD1 cDNA and recombinated plasmid pCMV-HA with segment of Homo sapiens MAP/MARK1 were cotransfected into HEK293 cells

the binding protein was detected.   Conclusion  The mutated SOD1 cDNA interacts with segment of Homo sapiens MAP/MARK1 at protein level in HEK293 cells.