9.B.206 The TMEM199 (TMEM199) Family 

Congenital disorders of glycosylation (CDGs) lead to diseases with aberrant protein glycosylation, some of which disturb Golgi homeostasis. TMEM199 is a human homolog of yeast V-ATPase assembly factor Vph2p (also known as Vma12p). Jansen et al. 2016 identified four people with different mutations in TMEM199. The adolescent individuals exhibited mild phenotypes of hepatic steatosis, elevated aminotransferases and alkaline phosphatase, hypercholesterolemia and low serum ceruloplasmin. Affected individuals showed abnormal N- and mucin-type O-glycosylation with reduced incorporation of galactose and sialic acid as seen in other Golgi homeostasis defects. TMEM199 localized to the endoplasmic reticulum and Golgi apparatus. Thus, TMEM199 is involved in Golgi homeostasis, and deficiency results in a hepatic abnormalities. Human TMEM199 is 208 aas long with two C-terminal TMSs.

This family belongs to the .



Jansen, J.C., S. Timal, M. van Scherpenzeel, H. Michelakakis, D. Vicogne, A. Ashikov, M. Moraitou, A. Hoischen, K. Huijben, G. Steenbergen, M.A. van den Boogert, F. Porta, P.L. Calvo, M. Mavrikou, G. Cenacchi, G. van den Bogaart, J. Salomon, A.G. Holleboom, R.J. Rodenburg, J.P. Drenth, M.A. Huynen, R.A. Wevers, E. Morava, F. Foulquier, J.A. Veltman, and D.J. Lefeber. (2016). TMEM199 Deficiency Is a Disorder of Golgi Homeostasis Characterized by Elevated Aminotransferases, Alkaline Phosphatase, and Cholesterol and Abnormal Glycosylation. Am J Hum Genet 98: 322-330.


TC#NameOrganismal TypeExample

TMEM199 of 208 aas and 2 C-terminal TMSs. Involved in protein glycosylation and Golgi homeostasis (Jansen et al. 2016).

TMEM199 of Homo sapiens


Vma12 family member of 302 aas and 2 C-termnal TMSs.

Vma12 of Drosophila melanogaster (Fruit fly)


TMEM199 homologue of 204 aas and 2 C-terminal TMSs.

TMEM199 homologue of Mucor circinelloides (Mucormycosis agent) (Calyptromyces circinelloides)


Uncharacterized protein of 251 aas and 2 TMSs

UP of Dictyostelium discoideum (Slime mold)


Uncharacterized protein of 252 aas and 2 C-terminal TMSs

UP of Chlamydomonas reinhardtii (Chlamydomonas smithii)


Uncharacterized protein of 213 aas and 2 C-terminal TMSs

UP of Schistosoma mansoni (Blood fluke)


TC#NameOrganismal TypeExample

Vacuolar ATPase assembly protein of 215 aas and 2 TMSs, Vph2 or Vma12, a TMEM199 homologue (Jansen et al. 2016).

Vph2 of Saccharomyces cerevisiae (Baker's yeast)


Vma12 of 205 aas and 2 TMSs

VMa12 of Kluyveromyces marxianus