The chromokinesin Kid (KIF22) forms a homodimer, moves processively along microtubules, and transports double-stranded DNA.

Kid (KIF22) forms a homodimer, moves processively along microtubules, and transports double-stranded DNA, challenging previous views of it as a monomeric, nonprocessive motor.

• Why it matters: Understanding the mechanisms of chromosome movement during mitosis is crucial for insights into cell division errors and related diseases. Clarifying Kid’s motor properties fills a key knowledge gap about its role in chromosome positioning.
• What they did: Researchers demonstrated that full-length Kid forms a homodimer via a conserved coiled-coil domain and moves processively along microtubules, also transporting DNA in vitro, supported by AlphaFold3 predictions.
• The result: These findings reclassify Kid as a processive, dimeric motor capable of DNA transport, providing new insights into its function during mitosis and potential implications for chromosome segregation fidelity.