Origin of rat β-globin haplotypes containing three and five genes

We have reported in rat three adult β-gene haplotypes containing either five or three genes. Detailed sequence analysis reveals that the leftmost gene is the major gene and that at the opposite end downstream lies the minor gene. All of the genes lying between them are minor-major hybrids indicating their origin by unequal crossing-over. In two haplotypes β-globin genes were found with an L1 element inserted directly into IVS2. The described results allow the formulation of a pathway of mutational events leading from the ancient two-β-gene rodent ancestor through a three-gene haplotype to five-gene haplotypes, one of which is postulated to have arisen in common laboratory strains since their capture in the wild.[https://academic.oup.com/mbe/article/7/5/407/1061225

Identification of procollagen mRNAs transferred to diazobenzyloxymethyl paper from formaldehyde agarose gels.

Poly A containing RNA isolated from embryonic chick calvaria was transferred from 6% formaldehyde 0.75% agarose gels to diazobenzyloxymethyl paper and the paper then hybridized to either nick translated pro alpha 1 collagen cDNA clones, pCg1 or pCg54, or to the nick translated pro alpha 2 collagen cDNA clone, pCg45. From the mobilities of the bands hybridizing most strongly to each, pro alpha 2 collagen mRNA was shown to be slightly larger than pro alpha 1 mRNA; they are 5100 and 4900 nucleotides long respectively. pCg54 also hybridized weakly to two bands of lower mobility, corresponding to RNAs 6.4 and 5.6 kb long. Neither pCg54 nor pCg45 hybridized to type II procollagen mRNA in poly A containing RNA isolated from embryonic chick sterna

A pool of nonpolysomal globin mRNAs in globin deficient reticulocytes of the anemic Belgrade rat

In anemia of the Belgrade rat ( b b) reticulocytes contain less than half of the normal amount of mRNA for seven adult rat globin chains. cDNA hybridization measurements of the relative sizes of polysomal and nonpolysomal pools of globin mRNAs in these cells show that 45% of all globin mRNA molecules are not used at any given time in protein synthesis. This implies a translational control which ensures a production of globin chains in a correct ratio despite a severe mRNA unbalance

Variant chromosomal arrangement of adult β-globin genes in rat

The genomic organization of three haplotypes of β-globin genes was determined to resolve the question of the number of those genes in rat. Haplotype a, found in inbred strain DA, has three genes or pseudogenes, while haplotypes b, found in AO, Y5 and Wistar strains, and c, found in Wistar strain, have five genes or pseudogenes each. In haplotypes b and c, the first gene is of βmajor type and the remaining four are of βminir type. Partial sequencing of six out of 13 genes shows that duplications of βminor genes are causing polymorphism in a number of genes. Also, in haplotype b two βminor genes have a 6.5-kb intron 2, while in haplotype c only one βminor gene contains such a large intron 2. The three structurally different haplotypes described are not interconvertible by single recombination events. The results indicate that the rat has the highest number of adult β-globin genes found in mammals so far

Limited polymorphism of both classes of MHC genes in four different species of the Balkan mole rat

We analyzed the restriction fragment length polymorphism of class I and class II MHC genes in DNA from 20 individuals belonging to the four different species of the complex of species of Balkan mole rats Spalax leucodon captured at four different localities in Yugoslavia. All populations were tested with four restriction enzymes and one conserved mouse probe for each of the two classes of MHC genes. The probes employed detect either limited polymorphism of class I genes or lack of polymorphic bands containing class II genes. Of the two other subterranean rodents that have been studied, four karyotype forms of the Israeli mole rat show polymorphism in both classes of MHC genes similar to the one found in all other mammals (Nižetić et al. 1985), and the Syrian hamster shows limited polymorphism of class I genes and high polymorphism of class II genes (McGuire et al. 1985). Balkan mole rats belong to a new group in this respect, different from all mammals studied so far, since they apparently show limited polymorphism of both classes of MHC genes