sperm-associated antigen 5 (astrin, mitotic spindle-associated protein p126, MAP126, Deepest, SPAG5)

Function

• necessary for normal spindle formation during mitosis
• homodimer, with a globular head domain & a long stalk
• homo-oligomer; the globular head domains associate, resulting in aster-like structures
• binds to microtubules in the mitotic spindle
• phosphorylated upon DNA damage, probably by ATM or ATR

Compartment

• cytoplasm, spindle, kinetochore
• an a punctate pattern in interphase cells
• during mitosis, detected at spindle poles during prophase, throughout the spindle in metaphase & anaphase, & at midzone microtubules in anaphase & telophase
• detected on kinetochores of chromosomes that have congressed

Expression

• highly expressed in testis
• detected at lowlevels in placenta, liver, pancreas, thymus & colon

More general terms

• kinetochore protein
• phosphoprotein

Database

• UniProt: http://www.uniprot.org/uniprot/Q96R06.html