Binds lactose. May play a role in fruiting body formation (By similarity). Homotetramer. Oligomerization is required for carbohydrate binding. Detected in extracellular matrix, cell wall and cytoplasmic membrane-bound bodies. Most abundant in fruiting bodies. Very low levels of expression in asexual vegetative mycelia. Most abundant prior to premeiotic S-phase, remains high from karyogamy to early pachytene, declines drastically by late pachytene and diplotene, and is undetectable by sterigma stage. Repressed by continuous light.