Iqub, encoding the IQUB protein, is highly and specifically expressed in murine testes. It plays a crucial role in sperm function, particularly in the assembly of the sperm radial spoke, which is important for sperm motility. It may be involved in regulating the activity of p-ERK1/2/RSPH3 pathway, and has potential connections to other biological processes related to cilia and flagella function [1].

Knockout (KO) and knockin (KI) mouse models of Iqub have been constructed to study its function. Iqub KO and KI mice mimic the infertility phenotype seen in affected individuals, with sperm from these models showing radial spoke defects. This indicates that Iqub is essential for the normal assembly of radial spokes in sperm flagella, and its deficiency leads to asthenospermia, a major cause of male infertility [1,2].

In conclusion, Iqub is critical for sperm radial spoke assembly and sperm motility, as demonstrated by model-based research. The Iqub KO and KI mouse models have significantly contributed to understanding its role in male infertility, expanding our knowledge of the genetic factors underlying asthenospermia and potentially providing a new genetic marker for the condition [1,2].