Cell fusion protein, AFF-1 of 589 aas and 2 TMSs, one N-terminial and one C-terminal (Soulavie and Sundaram 2016).  Required for cell fusion events during development including the fusion of anchor cells (AC), vulval A and vulval D rings, and late epidermal seam cells (Sapir et al. 2007). In response to environmental stressors, C. elegans enters a diapause state, termed dauer, which is accompanied by remodeling of sensory neuron receptive endings, dependent on AFF-1 (Sapir et al. 2007). In response to environmental stressors, C. elegans enters a diapause state, termed dauer, which is accompanied by remodeling of sensory neuron receptive endings, dependent on AFF-1 (Procko et al. 2011).