Protein ITFG3 also known as family with sequence similarity 234 member A (FAM234A) is a protein that in humans is encoded by the ITFG3gene.[1][2] Here, the gene is explored as encoded by mRNA found in Homo sapiens. The FAM234A gene is conserved in mice, rats, chickens, zebrafish, dogs, cows, frogs, chimpanzees, and rhesus monkeys.[3]Orthologs of the gene can be found in at least 220 organisms including the tropical clawed frog, pandas, and Chinese hamsters.[4] The gene is located at 16p13.3 and has a total of 19 exons. The mRNA has a total of 3224 bp and the protein has 552 aa.[5][3] The molecular mass of the protein produced by this gene is 59660 Da.[6] It is expressed in at least 27 tissue types in humans, with the greatest presence in the duodenum, fat, small intestine, and heart.[3]
A “Newfoundland deletion” or a0-thalassemia deletion has been found within the second intervening sequence of the FAM234A gene.[7] The gene is associated with multiple red blood cell phenotypes in African Americans – though the exact function or effect of the gene was not entirely clear.[8] Review of GeneCards’ current database on the FAM234A gene provided no additional elucidation on the function of the gene.[6]
FAM234A is located on Chromosome 16 (234,546 - 269, 943). It is 35,398 bases long, contains 11 exons, and is oriented on the plus strand in the 5' to 3' direction. Other aliases include ITFG3, C16orf9, and gs19.
There are no known paralogs of FAM234A.
The FAM234A gene is conserved in at least 220 organisms, with no evidence for conservation of the gene in single celled organisms. Listed below is a selection of orthologs with the estimated date of divergence from human lineage in million years ago (MYA), the accession number, and the % identity to human FAM234A. This list does not contain all of the known orthologs.
Selection of Organisms with FAM234A Orthologs
Common Name
Divergence from Human Lineage (MYA)
Accession Number
Identity to Human (%)
Rhesus Monkey
28.1
NP_001253283.1
95
White-tufted-ear marmoset
42.6
XP_009007067.1
86
House mouse
88
NP_001344823.1
86
Chinese Hamster
88
XP_003501607.1
77
Upper Galilee mountains blind mole rat
88
XP_008849023.1
74
Golden Hamster
88
XP_005081607.1
76
Giant Panda
94
XP_011224429.1
73
Horse
94
XP_014585783.1
74
Beluga Whale
94
XP_022450014.1
73
Chicken
320
XP_414950.2
45
Blue Tit
320
XP_023792271.1
43
Bengalese Finch
320
XP_021404267.1
44
Central Bearded Dragon
320
XP_020667631.1
43
Australian saltwater crocodile
320
XP_019395600.1
47
Tropical Clawed Frog
353
NP_001121517.1
35
Zebrafish
432
XP_001336768.2
31
Barramundi Perch
432
XP_018520114.1
34
Japanese Medaka
432
XP_020567870.1
33
Elephant Shark
465
XP_007906598.1
37
Rat
88
NP_001009701.1
72
mRNA
There are at least 11 FAM234A isoforms. Aside from the longest transcript, the other isoforms differ by truncation, primarily at the 3' end. This results in a wide variation in sequence length between isoforms.
Protein
File:Predicted Secondary Structure of FAM234A.pngPredicted Features of FAM234A Secondary Structure. Numbered according to amino acid in the FAM234A protein, areas where there is a predicted alpha-helix are highlighted in yellow. Areas that are predicted to be beta-strands are highlighted in green.
The FAM234A gene encodes a serine and leucine rich protein titled the "FAM234A Protein" or ITFG3. The encoded protein is 552 amino acids in length with a predicted molecular weight of 59,660Da and a basal isoelectric point of 5.84.[9] The FAM234A protein has a notable hydrophobic region from position 49-70 in the amino acid sequence that correlates with one of the two trans-membrane regions found on FAM234A.[10] FAM234A has membrane topology type 3a, indicating multiple trans-membrane regions with it's N-terminus facing the cytosol. The protein is predicted to be located in the endoplasmic reticulum, with portions of it found within the endoplasmic reticulum lumen.[10] Within the cell, FAM234A has also been localized to the ribosomes and nucleus.[11]
↑Waye JS, Eng B, Hanna M, Hohenadel BA, Nakamura L, Walker L (May 2017). "α0-Thalassemia Due to a 90.7 kb Deletion (-/-NFLD)". Hemoglobin. 41 (3): 218–219. doi:10.1080/03630269.2017.1369987. PMID28838269.
Flint J, Thomas K, Micklem G, Raynham H, Clark K, Doggett NA, King A, Higgs DR (March 1997). "The relationship between chromosome structure and function at a human telomeric region". Nature Genetics. 15 (3): 252–7. doi:10.1038/ng0397-252. PMID9054936.
Daniels RJ, Peden JF, Lloyd C, Horsley SW, Clark K, Tufarelli C, Kearney L, Buckle VJ, Doggett NA, Flint J, Higgs DR (February 2001). "Sequence, structure and pathology of the fully annotated terminal 2 Mb of the short arm of human chromosome 16". Human Molecular Genetics. 10 (4): 339–52. doi:10.1093/hmg/10.4.339. PMID11157797.
