Macaque interferon-induced transmembrane proteins limit replication of SHIV strains in an Envelope-dependent manner
Fig 2
Characterization of macaque IFITMs.
(A) A comparison of the chromosomal context of IFITM and IFITM-like genes in macaques and human. Top panel: Comparison of the human IFITM locus on chromosome 11 (abbreviated “ch11”) of the human reference genome and the corresponding loci in the indicated macaque genomes (chromosome 14 “ch14” for rhesus and crab-eating macaques, and Mnem_1.0 Scaffold195 for pig-tailed macaque). Exons are indicated as filled rectangles and introns as joined angled lines. Gene names are indicated in italics. Vertical alignment of conserved flanking genes NLRP6, PGGHG, B4GALNT4, and PKP3 across species is indicative of synteny. Humans encode IFITM2 (blue), a duplication of IFITM3, which is not present in the macaque genomes. The parental IFITM3 (orange, LOC105494127 in pig-tailed macaque) is present in human and macaques. Macaques genomes contain an additional copy of IFITM3 (indicated IFITM3A, LOC105494124, green) and an IFITM3 pseudogene (gray). Bottom panel: Two additional IFITM3-like genes identified in macaques in different chromosomal contexts. One IFITM3-like gene (indicated IFITM3L, LOC105473984, brown) is located in the intron of CPFAS on chromosome 16 (ch16). The other gene (indicated IFITM3L, LOC105466036, pink) is located in the intron of MCU on chromosome 9 (ch9). The corresponding loci in the human genome are indicated below and lack IFITM3-like genes. (B) A maximum likelihood tree of IFITM nucleotide sequences shows groupings of IFITM1, IFITM3 pseudogenes, and IFITM3/2. Tree is rooted on the IFITM1 group. Text colors correspond to rectangles depicting the same sequences in panel A. Nodes with bootstrap support greater than 90 are labeled. (C) Western blot analysis of Ptm lymphocytes treated with increasing concentrations of IFNα for 24 hours. The concentration of IFNα is indicated above each lane. Immunoblotting performed using anti-IFITM3/3A and anti-GAPDH antibodies.