TABLE 3.
Mammalian IFT-A ciliary phenotypes.
| IFT-A | Cilia structure | Cell type | Cilia localization of proteins | References |
| Core | ||||
| Ift144dmhd/dmhd (null) | Extremely short cilia | Neural tube, MEF | No Arl13B, ACIII, or SMO entry; IFT-B accumulation | Liem et al., 2012 |
| Ift144 ko or kd | Slightly shortened cilia with bulbous distal tip | RPE | Loss of IFT-A around basal body, no entry of SMO or ARL13B; IFT-B, BBS4 accumulation | Fu et al., 2016; Hirano et al., 2017 |
| Ift144twt/twt hypomorph | No obvious length defects | Neural tube, MEF | Decreased ACIII; slightly increased GLI2 at ciliary distal tip | Liem et al., 2012 |
| Ift122sopb/sopb (null) | Short with bulbous distal tip | Mouse node, MEF | Increased IFT-B, Gli2, Gli3 at distal tip; no TULP3 | Qin et al., 2011 |
| Ift122 ko | No cilia | RPE | Loss of IFT-A and GPR161 around basal body, normal IFT-B around basal body; no SMO entry | Takahara et al., 2018 |
| Ift140 cauli/cauli | Short with bulbous distal tip | Limb buds | Miller et al., 2013 | |
| Peripheral | ||||
| Ift121/Wdr35 mutant and ko | Shortened cilia with bulbous distal tip | Patient fibroblasts; RPE | Increased BBS4 and BBS5, Gli2, IFT-B, IFT-A, Kif3A; no ARL13B, INNP5E, SSTR3, MCHR1, serotonin receptor; reduced SMO | Fu et al., 2016; Duran et al., 2017 |
| Ift43 kd | Shortened cilia with bulbous distal tip | RPE | Increased IFT88, BBS4; no ARL13B | Fu et al., 2016 |
| Ift43 deficiency | Shortened cilia | Patient fibroblasts | Duran et al., 2017 | |
| Thm1/Ttc21baln/aln (null) or kd | Shortened with bulbous distal tip | Limb bud, MEF, 3T3-LT1, renal epithelial | IFT-B, IFT-A, BBS, SMO accumulation at distal tip; decreased Arl13B, INNP5E, IFT-A | Tran et al., 2008; Tran et al., 2014; Jacobs et al., 2020; Wang et al., 2020 |
| IFT139/Ttc21b ko | Normal cilia length with bulbous distal tip | RPE | IFT-B, IFT-A, SMO, GPR161 accumulation at distal tip | Hirano et al., 2017 |
| Thm2/Ttc21a-null | Normal | MEF | Normal | Wang et al., 2020 |
| Adaptor | ||||
| Tulp3 kd; cko and K407I (deficiency) | No length defects | RPE; renal epithelia | Decreased SSTR3 and MCHR1; severely reduced ARL13B, reduced polycystin 2 | Mukhopadhyay et al., 2010; Hwang et al., 2019; Legue and Liem, 2019 |
| Tulp3 ko | Shortened | RPE | No ARL13B or INNP5E | Han et al., 2019 |
SSTR3, somatostatin receptor 3; Mchr1, melanin-concentrating receptor 1; ACIII, adenylate cyclase type III.