8.A.60 The Transmembrane protein 139 (TMEM139) Family Human kidney anion exchanger 1 (kAE1) mediates Cl^-/HCO3^- exchange at the basolateral membrane of acid-secreting alpha-intercalated cells. Mutations in the SLC4A1 gene, encoding kAE1 (TC# 2.A.31.1.1), are associated with distal renal tubular acidosis (dRTA). Several studies have shown that impaired trafficking of the mutant kAE1 is an important molecular mechanism underlying the pathogenesis of dRTA. TMEM139 interacts with kAE1. Suppression of endogenous TMEM139 by small interfering RNA (siRNA) and over-expression of TMEM139 in HEK293T cells reduced and increased membrane localization of kAE1, respectively (Nuiplot et al. 2015). Thus, TMEM139 interacts with kAE1 and promotes its intracellular trafficking.
References:
Nuiplot, N.O., M. Junking, N. Duangtum, S. Khunchai, N. Sawasdee, P.T. Yenchitsomanus, and V. Akkarapatumwong. (2015). Transmembrane protein 139 (TMEM139) interacts with human kidney isoform of anion exchanger 1 (kAE1). Biochem. Biophys. Res. Commun. 463: 706-711.
Examples:
TC#	Name	Organismal Type	Example
8.A.60.1.1	TMEM139 protein of 216 aas and 2 N-terminal TMSs. Interacts with and promotes membrane localization of anioin exchanger 1 (AE1; SLC4A1) in human kidney cells (Nuiplot et al. 2015). It may be involved in cellular trafficking of proteins such as SLC4A1 (Nuiplot et al. 2015).		TMEM139 of Homo sapiens

8.A.60.1.2	TMEM139 of 274 aas and 2 TMSs		TMEM139 of Ophiophagus hannah (King cobra) (Naja hannah)

8.A.60.1.3	TMEM139 of 212 aas and 2 TMSs.		*TMEM139 of Ornithorhynchus anatinus* (Duckbill platypus)**

Examples:
TC#	Name	Organismal Type	Example
8.A.60.2.1	TMEM61 of 210 aas with 2 N-terminal TMSs.		TMEM61 of Homo sapiens

8.A.60.2.2	TMEM61 isoform X of 341 aas with 2 or 3 TMSs.		TMEM61 of Cuculus canorus

8.A.60.2.3	TMEM61 of 278 aas and 2 or 3 TMSs.		*TMEM61 of Meleagris gallopavo* (Wild turkey)**