"Self-nonself discrimination by the complement system mechanistic insights "

Dr. Arvind Sahu
National Centre for Cell Science (NCCS)

16th May 2019
2:30 pm

CDFD Seminar Hall,
3rd floor


The complement system discriminates 'self' from 'non-self' targets solely owing to the presence of complement regulators on the host cells, and therefore deficiencies, mutations and polymorphism in the complement regulatory proteins are linked to various diseases. The regulators that control complement activation on the host cell surface belong primarily to a family of proteins termed 'regulators of complement activation (RCA)'. These RCA proteins regulate complement by two functional mechanisms dubbed as decay-acceleration activity (DAA) and cofactor activity (CFA). Our efforts to systematically scan these RCA proteins by sequential mutagenesis employing deletion mutagenesis, domain swapping and site-directed mutagenesis approach have revealed that the basic functional units for DAA and CFA are modular and joining these units result in the formation of a larger composition with dual function. The molecular basis of the functioning of these units will be discussed.