In __SP__ , binding of cytoplasmic domain from __SP__ __NODE__ protein and mutant __NODE__ 2 [__NODE__] protein ( N terminal truncation 1 2 ) is the same as binding of mutant cytoplasmic domain ( Y1146F ) from __SP__ __NODE__ protein and mutant __NODE__ 2 [__NODE__] protein ( N terminal truncation 1 2 ) .