Regional localization of the fibronectin and gamma crystallin genes to mouse chromosome 1 by in situ hybridization

Genes for fibronectin, gamma crystallin, and isocitrate dehydrogenase-1 are syntenic in mouse, man, and cow. In an effort to physically locate this conserved chromosome region in the genomes of the respective species, we have localized the fibronectin and gamma crystallin genes to mouse chromosome 1, region C1-5 by in situ hybridization. In situ hybridization was conducted on metaphase chromosomes of bone marrow preparations of Rb 1.7 mice. These cells contain Robertsonian translocated chromosomes 1 and 7 as the only submetacentric chromosome in an otherwise acrocentric genome. Physically mapping these genes to mouse chromosome 1 now enables comparisons of the genetic map and the physical map on the proximal half of this chromosome. Genes in this conserved region of mouse chromosome 1 are also involved in resistance to intracellular pathogens, and the chromosomal localization of this region may facilitate the identification of homologous genes in other species.     

Mapping of alpha-spectrin on distal mouse chromosome 1

DNAs from different strains of inbred mice and feral Mus spretus were found to exhibit restriction fragment length polymorphisms (RFLP) when hybridized with a probe prepared from a c-DNA clone of the mouse alpha-spectrin (Spna-1) gene. Studies of five recombinant inbred strains and (C57BL/6 X M. spretus) F1 X C57BL/6 backcross mice demonstrated that these RFLPs were allelic and that Spna-1 is closely linked to Ly-9 and Ly-17 on the distal region of chromosome 1.     

Mapping of the bcl-2 oncogene on mouse chromosome 1

Two bcl-2 alleles have been identified in inbred strains of mice by restriction fragment length polymorphism (RFLP). Analysis of a bcl-2 RFLP in a series of bilineal congenic strains (C.D2), developed as a tool for chromosomal mapping studies, revealed linkage of bcl-2 to the Idh-1/Pep-3 region of murine chromosome 1. The co-segregation of bcl-2 alleles with allelic forms of two other chromosome 1 loci, Ren-1,2 and Spna-1, in a set of back-cross progeny, positions bcl-2 7.8 cM centromeric from Ren-1,2.     

Mapping Creb-1 to chromosome 1 in the mouse.

The gene CREB1 encoding the cyclic AMP response element DNA binding protein was previously assigned to human 2q32.3-q34. In this study, a panel of 207 backcross mice made between C57BL/10ScSn (=B10) females and (B10 x B10.L-Lsh)F1 males were used to map Creb-1 with respect to Cryg and Lsh/Vil on mouse chromosome 1. A reverse-transcribed, polymerase chain reaction-amplified cDNA probe covering bp 39 to 554 of the human sequence identified restriction fragment length polymorphisms with 7/18 restriction endonucleases used to digest whole genomic mouse DNA from the parental strains. BglII and DraI RFLPs for Creb-1 were scored on a subpanel of 16/207 known recombinants between Cryg and Lsh/Vil, yielding 2/16 recombinants between Cryg and Creb-1 and 14/16 recombinants between Creb-1 and Lsh/Vil. The 16/207 recombinants observed between Lsh/Vil and Cryg provide an estimated recombination frequency of 0.077 +/- 0.019, equivalent to a map distance of 7.7 +/- 1.9 cM. This is in good agreement with previously published map distances. The number of recombinants observed between Creb-1 and the other markers place Creb-1 approximately 1 cM distal to Cryg and 7 cM proximal to Lsh/Vil.     

Mapping of aminoacylase-1 and beta-galactosidase-A to homologous regions of human chromosome 3 and mouse chromosome 9 suggests location of additional genes.

Conserved linkage groups have been found on the X and autosomal chromosomes in several mammalian species. The identification of conserved chromosomal regions has potential for predicting gene location in mammals, particularly in humans. The genes for human aminoacylase-1 (ACY1, N-acylamino acid aminohydrolase, E.C.3.5.1.14), an enzyme in amino acid metabolism, and beta-galactosidase-A (GLB1, E.C.3.2.1.23), deficient in GM1-gangliosidosis, have been assigned to human chromosome 3. Using human-mouse somatic cell hybrids segregating translocations of human chromosome 3, expression of both ACY1 and GLB1 correlated with the presence of the p21 leads to q21 region of chromosome 3. In a previous study, assignment of these genes to mouse chromosome 9 used mouse-Chinese hamster somatic cell hybrids, eliminating mouse chromosomes. To approximate the size of the conserved region in the mouse, experiments were performed with recombinant inbred mouse strains. An electrophoretic variant of ACY-1 in mouse strains was used to map the Acy-1 gene 10.7 map U from the beta-galactosidase locus. These data suggest that there is a region of homology within the p21 leads to q21 region of human chromosome 3 and a segment of mouse chromosome 9. Since the mouse transferrin gene (Trf) is closely linked to the aminoacylase and beta-galactosidase loci, we predict that the human transferrin (TF) gene is on chromosome 3.     

Receptors for Fc epsilon and Fc gamma are linked on mouse chromosome 1

Recently isolated cDNA clones for the high affinity Fc epsilon receptors on mast cells and basophils (Fc epsilon RI alpha) and Fc gamma receptors on macrophages and lymphocytes (Fc gamma 2b/gamma 1R) are homologous members of the Ig supergene family. Analysis of the segregation of restriction fragment length polymorphism in crosses of inbred mice now establish that the structural genes encoding both Fc epsilon RI alpha and Fc gamma 2b/gamma 1R are indeed discrete genes and are linked at the distal end of mouse chromosome 1. This finding raises the possibility that a family of Fc receptors could be found in a region that is known to contain immunologically important markers of lymphocyte surface Ag and autoimmune defects.     

Mapping of glutenin and gliadin genes located on chromosome 1B of common wheat

Summary The inheritance of the high molecular weight (HMW) glutenins and of several gliadins controlled, respectively, by the long and short arms of chromosome 1B of common wheat was studied. Analysis was carried out on the progeny of two inter-varietal crosses in which the parental lines possessed differentially migrating subunits as revealed by sodium dodecyl sulphate polyacrylamide gel electrophoresis. No recombination event was detected either within the fraction of the HMW glutenins or among most of the gliadin subunits studied indicating that they are controlled by tightly linked gene clusters. One gliadin subunit (B30) showed 25.5% recombination frequency with the rest of the gliadin subunits and 23.5% recombination frequency with the fraction of the HMW glutenin subunits. It has been concluded that this subunit is controlled by a separate locus (Gld-B6), proximal to the major gliadin gene cluster on the short arm of chromosome 1B. Consequently, the recombination percentage between the glutenin loci and most of the gliadin loci was calculated as 49.0 and the distance in centi-Morgans (cM) as 53.6. The estimated distance in cM is very close to the observed recombination percentage. A genetic map of these storage protein genes is presented.     

Introduction of human gamma 1 immunoglobulin genes into fertilized mouse eggs

A rearranged human gamma 1 immunoglobulin gene was introduced into fertilized mouse eggs. The phage Ch4A-VCE-gamma 1 was constructed by ligating an EcoRI and BglII fragment of pBR322-CESSV(CE-1) containing the VDJ region with an EcoRI and BamHI fragment of Ch4A-HIg gamma 1-10 containing the gamma 1 constant region. About 200 copies of Ch4A-VCE-gamma 1 genes were introduced into fertilized mouse eggs. Of 489 eggs injected with these genes, 319 survived and were transferred to oviducts of foster mothers. Thirtyeight mice were born and were screened for the presence of human gamma 1 immunoglobulin genes by Southern blot hybridization. Five of these 38 mice had integrated human gamma 1 immunoglobulin genes. None of the human gamma 1 copies in each mouse had undergone deletions or rearrangements as judged by the Southern blotting patterns for several restriction enzymes. Human gamma 1 gene was present in several different tissues. All the mice tested so far transmit the human gamma 1 gene to a fraction of their offspring in an autosomal dominant manner. Spleen cells from transgenic mice were analyzed for immunoglobulin production by reverse plaque assay or immunofluorescence staining of cytoplasmic immunoglobulin, but synthesis and secretion of human gamma 1 chains could not be detected. No human gamma 1 immunoglobulin mRNA was detected in the liver and spleen of a transgenic mouse. The presence of the human gamma 1 immunoglobulin gene appeared to have no effect on the expression of endogenous mouse immunoglobulin genes.     

Mapping of PRM1 to human chromosome 16 and tight linkage of Prm-1 and Prm-2 on mouse chromosome 16

The protamines are small, arginine-rich nuclear proteins that replace histones and transition proteins late in the haploid phase of spermatogenesis in mammals. The two mouse genes encoding protamines--Prm-1 and Prm-2--have been molecularly cloned and mapped to mouse chromosome 16 (MMU 16). A cDNA clone of mouse Prm-1 that hybridized to the corresponding human gene was used to analyze a panel of somatic cell hybrids made between human lymphoblasts and the E36 hamster cell line. The human gene, which we have designated PRM 1, was syntenic with human chromosome 16 (HSA 16) and discordant with all other human chromosomes. Linkage analysis in the mouse was accomplished using the backcross (Czech II x BALB/c Pt) x Czech II to map Prm-1 and Prm-2 to a position near the 5' terminus of MMU 16. No recombination between Prm-1 and Prm-2 was observed among 89 progeny of the Czech II x BALB/c cross or among 94 progeny of the backcross (CBA/J x BALB/cJ) x BALB/cJ, demonstrating that the two loci are separated by less than 1.6 cM on MMU 16. This tight linkage may be of functional significance, as Prm-1 and Prm-2 are among a limited number of genes known to be expressed postmeiotically in male haploid germ cells.     

Mapping of genes controlling seed storage-proteins and cytological markers on chromosome 1R of rye

Summary Rye secalins, telomeric C-bands, and telocentric chromosomes were used as markers in the progeny of a test-cross in order to determine the position of seed storage-protein genes Glu-R1 and Gli-R1 with respect to the centromere and both telomeres of chromosome 1 R in rye. These genes were linked to the centromere (32.35±3.28% and 36.27±3.37% recombination, respectively). Glu-R1 was loosely linked to the telomere of the long arm (43.63±3.47% recombination), while Gli-R1 was closely linked to the telomere of the short arm (9.80±2.08% recombination). This finding supports the possibility that rye - and -secalin genes may be located on the satellites, as has been described in wheat for genes that code similar proteins. The importance of metaphase-I pairing failure and its consequences for the estimation of the recombination fraction are also discussed.     

Mapping of theHox-3.1 andMyc-1.2 genes on chromosome 15 of the mouse by restriction fragment length variations

Restriction endonuclease fragment length variations (RFLV) were detected by use of the cDNA probeHox-3.1 for the homeo box-3.1 gene and also thec-myc oncogene probe for exon 2. RFLV ofHox-3.1 were found inHindIII restriction patterns, and RFLV of theMyc-1.2 gene inEcoRV patterns. From the RFLV, theHox-3.1 andMyc-1.2 genes were mapped on chromosome 15. Three-point cross test data showed that the frequency of recombination is 26.4% betweenMyc-1.2 andGpt-1, 30.2% betweenGpt-1 andGdc-1, and 9.4% betweenGdc-1 andHox-3.1. The following order of these genes is proposed,Myc-1.2—Gpt-1—Gdc-1—Hox-3.1. All laboratory strains carry theHox-3.1 ^a andMyc-1.2 ^a alleles. Among strains of wild origin,domesticus strains carry only theHox-3.1 ^a andMyc-1.2 ^a alleles, as do the laboratory strains. One strain ofbrevirostris carries theHox-3.1 ^a andMyc-1.2 ^b alleles. Other wild subspecies from Europe and Asia,M. m. musculus, M. m. castaneus, M. m. molossinus, Chinese mice of wild origin, andM. m. yamashinai carry theHox-3.1 ^b andMyc-1.2 ^b alleles.     

Mapping of Abll within a conserved linkage group on distal mouse chromosome 1 syntenic with human chromosome 1 using an interspecific cross

A human Abelson related gene (ABLL) cDNA clone was used to detect restriction fragment length polymorphisms (RFLPs) on mouse Southern blots. Abll was mapped to mouse chromosome 1 by analysis of segregation with other distal chromosome 1 genetic polymorphisms by using a panel of DNAs from [(C3H/HeJ-gld/gld x Mus spretus) F1 x C3H/HeJ-gld/gld] interspecific backcross mice. The data indicate the following gene order: (centromere)-CD45-6.5 cM-Lamb-2-1 cM-Abll-2 cM-At-3. The results extend the analysis of a large conserved linkage group spanning nearly 30 cM on distal mouse chromosome 1 syntenic with human chromosome 1q21-32. Within this linkage group similar relative positions have been characterized in both species for C4BP, REN, CD45, LAMB2, ABLL, AT3, APOA2, and SPTA.     

Somatic cell mapping and restriction fragment analysis of bovine genes for fibronectin and gamma crystallin

DNAs from cow-hamster and cow-mouse somatic hybrid cells segregating bovine chromosomes have been analyzed by Southern blotting and hybridization with human fibronectin and gamma crystallin probes. Concordancy of retention of these bovine genes was compared to cattle isozyme loci representing previously described syntenic groups. Bovine fibronectin (FNI) and gamma crystallin (CRYG) fragments were concordant with each other and with isocitrate dehydrogenase 1 (IDH1), representing the bovine syntenic group U17. The syntenic relationship of these genes is conserved on human chromosome 2q and also on mouse chromosome 1. In addition, bovine RFLPs were identified with both fibronectin and gamma crystallin probes. These polymorphisms will be used to study recombination between the syntenic loci in pedigreed herds and to mark a segment of the bovine genome that is likely homologous to the Lsh region of mouse chromosome 1, which confers resistance in mice to several intracellular parasites.     

Linkage of genes for laminin B1 and B2 subunits on chromosome 1 in mouse

Summary We have used cDNA clones for the B1 and B2 subunits of laminin to find restriction fragment length DNA polymorphisms for the genes encoding these polypeptides in the mouse. Three alleles were found forLamB2 and two forLamB1 among the inbred mouse strains. The segregation of these polymorphisms among recombinant inbred strains showed that these genes are tightly linked in the central region of mouse Chromosome 1 betweenSas-1 andLy-m22, 7.4±3.2 cM distal to thePep-3 locus. There is no evidence in the mouse for pseudogenes for these proteins. This work was supported by U. S. Public Health Service Grant GM28464 to R.W.E. Editor's Statement Investigation into the biosynthesis of laminin indicates that several different polypeptides are assembled to form the intact molecule. This paper represents an extension of previous work which takes a genetic approach to further define the relationships among the polypeptides involved. Gordon H. Sato     

Additional mapping of mouse chromosome 2 genes

The purpose of this work was to elucidate the genetic fine structure of the central portion of mouse chromosome (Chr) 2. Seven Chr 2 congenic mouse strains [B10.PA(L)-pa we un a ^t , B10.PA(L)-pa A ^w , B10.PA(L)-we un a ^t , B10.PA(J)-pa a, B10.FS-we A ^w , B10.C-we A ^w , and B10.YBR-a] were produced. Breeding studies were carried out using strains B10.PA(L)-pa we un a ^t and B10.LP-H-13 ^b to accurately determine the recombination frequencies between marker genes pa and we (1.9%±0.3), we and un (8.8%±0.5), and un and a ^t (4.5%±0.4) of strain B10.PA(L)-pa we un a ^t . These strains and other Chr 2 congenic strains were typed for immunologically defined loci using monoclonal antibody (mAb) C23 reactive with the gene product of B2m ^b T-lymphocyte clone C1 reactive with the gene product of H-3 ^a and H-3 ^c , and lymphocyte clone H1.8 reactive with the gene product of Hd-1 ^a . B2m and H-3 typing located a recombinational event separating [pa B2m H-3] from we (the order of bracketed genes is not known). Hd-1 typing indicated that Hd-1 maps distal to [H-42, H-44] and proximal to un. The gene order [pa, B2m, H-3], we, [H-42, H-45], Hd-1, un, H-13, a ^t , with H-44 mapping centromeric to Hd-1, is indicated by the data. Address correspondence and offprint requests to: R. J. Graff.     

Cloned embryonic DNA sequences flanking the mouse immunoglobulin C gamma 3 and C gamma 1 genes

To investigate the DNA surrounding genes for immunoglobulin heavy chain constant (CH) regions, we have isolated two clones bearing a C gamma 3 gene and two bearing a C gamma 1 gene from a library of mouse embryo DNA fragments. The C gamma 3 clones span 8.6 kilobase pairs (kb) on the 5' side of the gene and 6.7 kb on its 3' side, while the C gamma 1 clones together span 13 kb of 5' flanking sequence and 2.5 kb of 3' flanking sequence. Restriction mapping of the C gamma 3 gene indicates that intervening sequences divide the gene into segments of domain size, as in other CH genes. Hybridization of clone fragments to restriction digests of mouse DNA indicates that both the C gamma 1 and C gamma 3 genes probably occur as single copies in the genome. Moreover, the entire cloned sequences on the 5' side of both genes appear to be unique in the genome, indicating that no large common sequences flank CH genes. Restriction data suggest that the C gamma 3 gene is 37-40 kb 5' to the C gamma 1 gene.     

Regional mapping on human genes for phosphoglucomutase-1 on chromosome 1 and beta-glucuronidase on chromosome 7 using mouse x human hybrids.

Two independent mouse-human somatic cell hybrid clones contained different, de novo chromosome rearrangements involving the short arm of human chromosome 1. One hybrid clone contained a translocation between human chromosomes 1 and 7; the other clone contained a rearrangement product between human chromosomes 1 and 14. Analysis of these clones for expression of genes previously assigned to chromosome 7 and to the short arm of chromosome 1 provided evidence for localization of PGM--1 in segment 1p22.1 leads to 1p31.1, AK--2, ENO--1 and UMPK in region 1pter leads to 1p31.1, and GUS in region 7 pter leads to 7q22. The results have been used to examine the relationship between cytologic and genetic map distances on the short arm of chromosome 1.