Protects actin filaments from depolymerization. Interacts with ACTN2 (By similarity). Interacts with F-actin. Colocalizes with actin stress fibers. Xin repeats bind F-actin. 'Xin' means 'heart' in Chinese. Belongs to the Xin family. Contaminating sequence. Potential poly-A sequence. Truncated N-terminus. Contaminating sequence. Potential poly-A sequence. Contaminating sequence. Contaminating sequence.