MSP58 is a 462 amino acid protein that localizes to the nucleus and contains one FHA domain. Expressed at high levels during the S phase of the cell cycle and present in testis, prostate, thymus, spleen and colon, MSP58 functions to modulate the transcriptional activity of Daxx (a transcriptional repressor) by recruiting Daxx to the nucleolus. Additionally, MSP58 may play a role in the inhibition of TERT telomerase activity, further implicating MSP58 as an important protein in transcriptional regulation. The gene encoding MSP58 maps to human chromosome 12 and is expressed as multiple alternatively spliced isoforms. Encoding over 1,100 genes within 132 million bases, chromosome 12 makes up about 4.5% of the human genome and is associated wirh hypochondrogenesis, achondrogenesis and Kniest dysplasia.