Component of the IFT complex A (IFT-A), a complex required for retrograde ciliary transport (PubMed:28479320). Moves along the ciliary axoneme and is involved in the assembly, localization and the movement of other intraflagellar transport (IFT) proteins along the cilia axoneme (PubMed:16957054, PubMed:22922713). May also associate with the BBSome complex in order to mediate ciliary transport (PubMed:22922713). Regulates cilia biogenesis, morphology and sensitivity to environmental cues (PubMed:16957054, PubMed:22922713). Component of the IFT complex A (IFT-A) composed of at least che-11, daf-10, dyf-2, ift-139, ift-43 and ifta-1. Expressed in ciliated sensory neurons. Defects in cilium morphology and mislocalization of intraflagellar transport proteins. Specifically, phasmid cilia are shorter compared to wild-type, ciliary IFT A complex proteins such as che-11, osm-5 are mislocalized, and the transport and accumulation of the ciliary IFT B complex protein che-13 is impaired. Mutants also display a strong osmosensory (osm) phenotype with an aversion to high osmolarity, and they exhibit impaired chemotaxis in response to volatile odorants such as pyrazine and iso-amyl alcohol.