Isoform 1 is highly expressed in adult and fetal heart, skeletal muscle, and at a much lower levels in adipose tissue and in aorta. Undetectable in other tissues. Isoform 2 and isoform 3 are poorly detected in heart.
Belongs to the small heat shock protein (HSP20) family.
Cytoplasm. Nucleus. Nucleus > Cajal body. Resides in sub-nuclear structures known as SC35 speckles or nuclear splicing speckles.