HEAT repeats can form alpha solenoids, a type of solenoid protein domain found in a number of cytoplasmic proteins.

[4] HEAT repeats form extended superhelical structures which are often involved in intracellular transport; they are structurally related to armadillo repeats.

The nuclear transport protein importin beta contains 19 HEAT repeats.

Representative examples of HEAT repeat proteins include importin β (also known as karyopherin β) family,[5] regulatory subunits of condensin and cohesin,[6] separase,[7] PIKKs (phosphatidylinositol 3-kinase-related protein kinases) such as ATM (Ataxia telangiectasia mutated) and ATR (Ataxia telangiectasia and Rad3 related),[8][9] and the microtubule-binding protein XMAP215/Dis1/TOG[10] and CLASP.

[11] Thus, cellular functions of HEAT repeat proteins are highly variable.