The KIND (kinase non-catalytic C-lobe domain) is a putative protein interaction domain, which has been identified as being similar to the C-terminal protein kinase catalytic fold (C lobe) (see ).The presence of the KIND domain at the N terminus of signalling proteins and the absence of the active site residues in the catalytic and activation loops suggest that it folds independently and is likely to be non-catalytic. The occurrence of the domain only in metazoa implies that it has evolved from the catalytic protein kinase domain into an interaction domain possibly by keeping the substrate-binding features [, ]. In SPIRE1 (protein spire homologue 1) this domain interacts with FMN2 (formin-2) [, ].
