Lamas in loops

Students of cell biology could be excused for thinking that laminin biology evolved purely to vex them. Multiple different laminins—combinations of α, β, and γ subunits that make up at least 15 different versions of this heterotrimeric protein—are expressed in different places at different times, making a sensible analysis of this protein family a challenge. Most researchers have started with knockout experiments, but it is hardly surprising when a knockout defect correlates with the time and place of normal expression. Perhaps any laminin would suffice in the deleted laminin's place.

Now, Kikkawa et al. (page 187) find that this is not the case. They uncover a specialized function for the laminin α5 isoform (not to be confused with laminin-5) during development of the kidney...