Function
Increased sodium tolerance protein 1 (Ist1) is a family member of the transport-III (ESCRT-III) forming high-order helical structures with CHMP1B which are required in remodeling membranes during abscission[1].
Increased sodium tolerance protein 3 (Ist3) or U2 snRNP component IST3 (Ist3) is part of the spliceosome which is involved in transcription and pre-mRNA splicing. Ist3 interacts with human elongation factors and strongly stimulates polymerase elongation[2].
Disease
Somatic mutations in Ist3 have been found in various malignancies like breast cancer, pancreatic cancer, uveal melanoma and others[3].
Structural highlights
The structure of the yeast Ist1 N-terminal complex with ESCRT-III subunit Did2 which is part of a high-order helical structure shows pointing toward the Did2 helix. of Ist1 were found by mutational studies to interact with Did2[4]. .
