Isolation of proteins related to the Rh polypeptides from nonhuman erythrocytes.

Abstract

It is thought that the Rh antigens may be important in maintaining normal erythocyte membrane integrity. Despite their name, Rh antigens are serologically present only on human erythrocytes. Rh structural polymorphisms are known to reside within a family of nonglycosylated M, 32,000 integral membrane proteins that can be purified by hydroxylapatite chromatography. M, 32,000 integral membrane proteins were purified similarly from erythrocyte membrane vesicles prepared from rhesus monkeys, cows, cats, and rats, but could not be purified from human Rhw erythrocytes, a rare syndrome lacking Rh antigens. The purified M, 32,000 polypeptides were labeled with 1251, digested with chymotrypsin, and found to be 30-60% identical to human Rh polypeptides when compared by two-dimensional iodopeptide mapping. The physiologic function of the Rh polypeptides remains to be identified; however, the existence of related proteins in nonhuman erythrocytes supports the concept that the Rh polypeptides are erythrocyte membrane components of fundamental significance.

Molecular characterization of the rh-like locus and gene transcripts from the rhesus monkey (Macaca mulatta)

“…4). The strong similarities observed between sequences of macaque and human Rh-polypeptides are in accordance with the resemblance between two-dimensional iodopeptide maps of human and macaque Rh-related polypeptides (Saboori et al 1989). Hydropathy plot calculations (Engelman et al 1986) suggest that the M. mulatta Rh-like proteins have a membrane organization similar to the human Rh proteins with multispanning hydrophobic transmembrane domains (Cherif-Zahar et al 1990;Avent et al 1990;Le Van Kim et al 1992).…”

“…The Rh-like proteins presumably inserted in the red cell membrane would account for the reactivity of the M. mulatta red blood cells with two monoclonal antibodies (anti-Rh29) that recognize nonpolymorphic epitopes at the red cell surface of human and nonhuman primates (Socha and Ruffi6 1990). Furthermore, these polypeptides may correspond to the Rh analog protein of 32 kDa isolated from rhesus monkey erythrocyte membranes (Saboori et al 1989). Among the 95-and 90-amino-acid substitutions found between the M. mulatta and the human D and Cc/Ee proteins, respectively, only 11 and nine are within the first 100 residues and only three and four within the last 40 amino acids, indicating a high degree of conservation of the N H zand COOH-terminal regions of the Rh-related proteins ( Fig.…”

“…Human anti-c antibodies agglutinate gibbon, chimpanzee, orangutan, and gorilla red cells whereas human anti-D react only with chimpanzee, orangutan, and gorilla cells (Wiener et al 1964;Shaw 1986;Socha and Ruffi6 1990). Analogs of nonhuman Rh proteins have also been described recently in monkey, cow, cat, and rat as 32-kDa erythrocyte polypeptides (Saboori et al 1989). All these studies established that other species than man and apes may carry Rh-like proteins that have not been yet characterized.…”

Assignment of the chromosomal locus of the human 30-kDal Rh (Rhesus) blood group-antigen-related protein (Rh30A) to chromosome region 1p36.13→p34

“…1, lane 8) show that a gene related to Rh30A is present in the mouse. This observation is consistent with the conclusions of studies (Saboori et al, 1989) showing that 30-kDal proteins with properties similar to the Rh30A protein could be isolated from the red cells of several nonhuman species, including the cow, cat. and rat.…”

Characterization of the Mouse Rh Blood Group Gene

“…Overall, the human and mouse Rh proteins are 58% identical at the amino acid level and 71% identical at the nucleotide level. Early work based on two-dimensional iodopeptide mapping had predicted that rodent erythrocytes had polypeptides that were 30 -60% identical to human Rh (9). Figure 1 shows an alignment of the amino acid sequences of mouse, humans, nonhuman primates, and bovine.…”