Gene expression comparison among affected and unaffected areas and normal scalp shows that some genes are downregulated in hair follicle cycling, lipid homeostasis, and peroxisome biogenesis, including PEX3 and PEX16, and some genes involved in the inflammatory cascade and apoptotic pathways are upregulated.
They require peroxins (PEXs) for their biogenesis, especially PEX3 and PEX16, which are both quite specific to PPAR-[gamma].
An alternative strategy, i.e., the homology search by screening the expressed sequence tag database using yeast PEX genes, successfully made it feasible to isolate human orthologue genes responsible for PBDs: (22), (24), (34) PEX1, (55), (56) PEX3, (57) PEX5, (58) PEX6, (59) PEX7, (60)-(62) PEX10, (63),(64) PEX12, (65) PEX13, (66) PEX14, (67) and PEX16. (68),(69)
Defects of PEX3, PEX16 and PEX19 encoding membrane-assembly peroxins lead to absence of ghosts and cause ZS phenotypes.
(1998) Mutation in PEX16 is causal in the peroxisome-deficient Zellweger syndrome of complementation group D.
(1997) Enlarged peroxisomes are present in oleic acid-grown Yarrowia lipolytica overexpressing the PEX16 gene encoding an intraperoxisomal peripheral membrane peroxin.
Complementation groups (CGs) and PEX genes of peroxisome deficiencies Gene CG PBD CHO mutants US/EU Japan PEX1 1 E ZS, NALD *, IRD * Z24, ZP107 PEX2 10 F ZS, IRD * Z65 PEX3 12 G ZS ZPG208 PEX5 2 ZS, NALD ZP105 *, ZP139 PEX6 4(6) C ZS, NALD * ZP92 PEX7 11 R RCDP ZPG207 PEX10 7(5) B ZS, NALD PEX11[beta] 16 ZS PEX12 3 ZS, NALD, IRD ZP109 PEX13 13 H ZS, NALD * ZP128 PEX14 15 K ZS ZP110 PEX16 9 D ZS PEX19 14 J ZS ZP119 PEX26 8 A ZS, NALD *, IRD * ZP124, ZP167 ZP114 Gene Ps-memb.
(2015) Multiple domains in PEX16 mediate its trafficking and recruitment of peroxisomal proteins to the ER.
(2011) Sec16B is involved in the endoplasmic reticulum export of the peroxisomal membrane biogenesis factor peroxin 16 (Pex16) in mammalian cells.