Locus determining the human sperm-specific lactate dehydrogenase,LDHC, is syntenic with LDHC

From the data presented in this report, the human LDHC gene locus is assigned to chromosome 11. Three genes determine lactate dehydrogenase (LDH) in man. LDHA and LDHB are expressed in most somatic tissues, while expression of LDHC is confined to the germinal epithelium of the testes. A human LDHC cDNA clone was used as a probe to analyze genomic DNA from rodent/human somatic cell hybrids. The pattern of bands with LDHC hybridization is easily distinguished from the pattern detected by LDHA hybridization, and the LDHC probe is specific for testis mRNA. The structural gene LDHA has been previously assigned to human chromosome 11, while LDHB maps to chromosome 12. Studies of pigeon LDH have shown tight linkage between LDHB and LDHC leading to the expectation that these genes would be syntenic in man. However, the data presented in this paper show conclusively that LDHC is syntenic with LDHA on human chromosome 11. The terminology for LDH genes LDHA, LDHB, and LDHC is equivalent to Ldhl, Ldh2, and Ldh3, respectively.     

Mapping of human lactate dehydrogenase-A, -B, and -C genes and their related sequences: the gene for LDHC is located with that for LDHA on chromosome 11

Human testis-specific lactate dehydrogenase-C (LDHC) gene-related sequences are located with the LDHA gene on chromosome 11. The LDHB gene is on chromosome 12. Chromosomes 1, 2, 4, 9, and 10 appear to contain LDHA gene-related sequences, whereas the X chromosome and chromosome 13 possess LDHB gene-related sequences.     

Gene assignments and syntenic groups in the sacred baboon (Papio hamadryas)

Eighteen genes were assigned to chromosomes in the sacred baboon, Papio hamadryas, by their concordant segregation with the chromosomes in a set of baboon X Chinese hamster somatic cell hybrids. ACY1 was assigned to P. hamadryas chromosome 2 (PHA 2); SOD1 and MDH2 to PHA 3; ME1 and SOD2 to PHA 4; NP, MPI, PKM2, and HEXA to PHA 7; PP to PHA 9; ADA and ITPA to PHA 10; LDHB and TPI1 to PHA 11; MDH1 to PHA 13; ESD to PHA 17; and GPI and PEPD to PHA 20. Regional assignments were possible for ACY1 (PHA 2pter----q1) and MDH2 and SOD1 (PHA 3p). Five other independently segregating markers or syntenic groups (PGD, PGM1; and PEPC; PGM2 and PEPS; IDH1; LDHA and ACP2; and GSR) were also identified. Gene assignments and syntenic groups described in P. hamadryas are compared to those found in P. papio, the rhesus monkey, and man. A possible primate model for human lymphoid disease is discussed.     

Defining the locus of origin of a genetically determined electrophoretic variant of a multilocus enzyme system; the calcutta-1 of human LDH system is a B-locus variant

Summary Six (four Hindus, one Sikh, and one Muslim) out of 213 individuals originating from different parts of the Indian subcontinent (namely, Andhra Pradesh, Maharashtra, Uttar Pradesh, East Punjab, and West Punjab) were found to be Calcutta-1 (CAL1) variants of lactate dehydrogenase (LDH). The CAL1 variant was originally described (and thus, generally believed at present) as an allelic variant at the LDHA locus in chromosome 11. By using an improved Cellogel electrophoretic procedure the isozyme patterns observed in the erythrocytes and leukocytes of the variant have indicated that the CAL1 is not a variant of LDHA but that of LDHB, a chromosome 12 marker. This suggestion was supported by the isozyme patterns of LDH in a set of segregating clones of man-mouse somatic cell hybrids with the variant as human partner. Moreover, the variant cosegregated consistently with the human chromosome 12 and with the markers firmly assigned to the latter but not with human chromosome 11 or its markers in these hybrids. These results confirmed that the CAL1 is an LDHB variant.     

Localization of the photoreceptor gene ROM1 to human chromosome 11 and mouse chromosome 19: sublocalization to human 11q13 between PGA and PYGM.

Rom-1 is a retinal integral membrane protein that, together with the product of the human retinal degeneration slow gene (RDS), defines a photoreceptor-specific protein family. The gene for rom-1 (HGM symbol: ROM1) has been assigned to human chromosome 11 and mouse chromosome 19 by Southern blot analysis of somatic cell hybrid DNAs. ROM1 was regionally sublocalized to human 11p13-11q13 by using three mouse-human somatic cell hybrids; in situ hybridization refined the sublocalization to human 11q13. Analysis of somatic cell hybrids suggested that the most likely localization of ROM1 is in the approximately 2-cM interval between human PGA (human pepsinogen A) and PYGM (muscle glycogen phosphorylase). ROM1 appears to be a new member of a conserved syntenic group whose members include such genes as CD5, CD20, and OSBP (oxysterol-binding protein), on human chromosome 11 and mouse chromosome 19. Localization of the ROM1 gene will permit the examination of its linkage to hereditary retinopathies in man and mouse.     

Creation of a clone panel of fox x Chinese hamster somatic cell hybrids and chromosome mapping of genes for LDHA, LDHB, GPI, ESD, G6PD, HPRT, alpha-GALA in the silver fox

A clone panel of fox-hamster somatic cell hybrids which can be used for fox gene mapping was set up. Analysis of patterns of chromosome-enzyme segregation made it possible to assign gene GPI to chromosome 1, LDHA to chromosome 11, LDHB to chromosome 8, ESD to chromosome 6 and G6PD, HPRT, alpha-GALA to chromosome X.     

cDNA cloning of pig testicular lactate dehydrogenase-C, thermal stability of the expressed enzyme, and polymorphism among strains

Pig testicular lactate dehydrogenase-C (LDHC) cDNA was cloned and sequenced. The deduced sequence of 332 amino acids from pig LDHC shows 73% and 67% identity with that of pig LDHA (muscle) and LDHB (heart) respectively, whereas pig LDHA and LDHB isozymes shows 74% sequence identity. Pig and mouse LDHC cDNAs were subcloned into bacterial expression vector, and the expressed pig LDHC isozyme was shown to be as thermally stable as mouse LDHC isozyme. Pig genomic DNAs from Chinese Meishan, English Yorkshire, Danish Landrace and American Duroc were shown to exhibit polymorphic sites for restriction enzymes EcoRI, BamHI and PstI.     

The thyroglobulin gene is syntenic with the MYC and MOS protooncogenes and carbonic anhydrase II and maps to chromosome 14 in cattle

Using a panel of bovine x Chinese hamster hybrid somatic cells, sequences homologous to genes spanning human chromosome arm 8q have been syntenically assigned in cattle. Thyroglobulin (TG), carbonic anhydrase II (CA2), and the protooncogenes MYC and MOS were assigned to a newly identified bovine syntenic group, U23. Additionally, in situ hybridization of the thyroglobulin probe to bovine metaphase chromosomes revealed this syntenic group to be on bovine chromosome 14 and the bovine thyroglobulin gene to reside at 14q12----q15.     

不同海拔牦牛骨骼肌中乳酸脱氢酶三种亚基基因表达的比较

为了阐明高原低氧对牦牛（Bos mutus）骨骼肌中乳酸脱氢酶（LDH）三种亚基基因（LDHA、LDHB和LDHC）表达的影响,本实验分别选取高海拔（4 200 m）、中海拔（3 200 m）和低海拔（1 900 m）三个海拔位置养殖的临床健康成年雄性牦牛各5头,采用实时荧光定量PCR(qRT-PCR)和蛋白质印迹法检测牦牛骨骼肌中LDH三种亚基基因的m RNA表达和蛋白表达水平。结果表明,随海拔的升高,牦牛骨骼肌中LDHA m RNA的表达逐渐下降;LDHB m RNA先降低后升高,在高海拔组牦牛中表达最高,相对表达量为2.82±0.12,与低海拔组（1.01±0.07）、中海拔组（0.73±0.06）牦牛LDHB mRNA表达量差异显著（P <0.05）;LDHC mRNA的表达量随海拔的升高呈下降趋势,且低海拔组（1.10±0.16）、中海拔组（0.86±0.16）、高海拔组（0.69±0.12）组间两两相比均差异显著（P <0.05）。LDHA和LDHC蛋白表达量随海拔的升高呈下降趋势,且LDHA蛋白表达量在低海拔组（1.00±0.00）、中海拔组（0.88±0.0...     

Further data on chromosomal assignments of pig enzyme loci LDHA, LDHB, MPI, PEPB and PGM1, using somatic cell hybrids

Summary. Clear interspecies differentiation between the chromosomes in pig-mouse somatic cell hybrids was achieved by using the THA-technique for the cytogenetic analysis. The assignments of LDHB and MPI to pig chromosomes nos 5 and 7 respectively, reported previously, were confirmed by analysis of 34 hybrid clones. The LDHA, PEPB and PGM1 genes were assigned to pig chromosomes nos 2, 5 and 6 respectively. Both LDHB and PEPB were indicated to be located on the long arm, except the most proximal part, of pig chromosome no. 5. The proposed synteny between LDHB and PEPB in pigs is in accordance with the synteny observed between these two loci in several other mammalian species.     

Assignment of the gene for carboxypeptidase A to human chromosome 7q22→qter and to mouse chromosome 6

Summary A rat cDNA probe for preprocarboxypeptidase A was used to follow the segregation of the human gene for carboxypeptidase A (CPA) in 49 human x mouse somatic cell hybrids using Southern filter hybridization techniques. CPA was assigned to human chromosome 7q22qter. Similarly, the probe was used to follow the segregation of the mouse gene for carboxypeptidase A (Cpa) in 19 mouse x Chinese hamster somatic cell hybrids. Cpa was assigned to mouse chromosome 6. The gene for carboxypeptidase A forms part of a syntenic group that is conserved in man and mouse.Preliminary chromosomal assignments of carboxypeptidase A in man and mouse have been made in abstract (Honey et al. 1983a, b)     

Mapping of the human ribonuclease inhibitor gene (RNH) to chromosome 11p15 by in situ hybridization

Ribonuclease inhibitor (RNH) is a protein that binds tightly to ribonucleases in cells and may be essential in the control of mRNA degradation and gene expression. The human RNH gene has been regionally localized to chromosome band 11p15 by in situ hybridization. A human placental cDNA was used to construct a 600-bp probe, which was then radiolabeled with tritium for in situ hybridization to human metaphase chromosomes. Localization of the RNH gene to 11p15, and possibly to 11p15.5, adds to a large number of genes assigned to this band, including 10 structural genes. This chromosomal region also represents an evolutionarily conserved syntenic group in the owl monkey, mouse, rat, and cow. Thus, regional assignment of RNH could facilitate the understanding of this gene and its association with ribonucleases, and perhaps extend a conserved syntenic region in mammalian genomes.     

The structural gene for the M1 subunit of ribonucleotide reductase maps to chromosome 11, band p15, in human and to chromosome 7 in mouse

The genes for the M1 subunit of the enzyme ribonucleotide reductase have been mapped in the human and the murine species by use of two independently derived mouse cDNA clones. Southern blot analysis of rodent x human somatic cell hybrid DNAs confirmed the assignment of RRM1 to the short arm of human chromosome 11. In situ hybridization to human metaphase chromosomes revealed a peak of silver grains over the distal third of band 11p15, a region corresponding to subbands p15.4----p15.5. The mouse Rrml locus was assigned to chromosome 7, where it forms part of a conserved syntenic group of at least seven other genes assigned to human chromosome band 11p15.     

Chromosome assignment of the gene loci ETS1 and THY1 in the owl monkey

Our previous assignment of the gene loci HBB, HRAS1, INS, PTH, LDHA, and CAT to owl monkey chromosome 19 of karyotype VI (K-VI) indicated a putative homology of this owl monkey chromosome with the short arm of human chromosome 11 (HSA 11p). To investigate further the extent of shared homology, we localized in the owl monkey complement two genes known to be on HSA 11q. Segregation analysis of ETS1 and THY1 homologous DNA in three karyotypically different panels of rodent x owl monkey somatic cell hybrids provided evidence for the syntenic assignment of these loci to homologous chromosomes of three owl monkey karyotypes, namely, chromosomes 4 (K-VI), 3 (K-II), and 5 (K-V). The results indicate a disruption of syntenic gene loci on the distal portion of HSA 11q from 11p during primate evolution.     

New gene assignments in the baboon and new chromosome homoeologies with man

Eight new gene assignments were demonstrated in the baboon (Papio papio, PPA) by cosegregation analysis of twelve hybrid clones obtained by fusion between PPA fibroblasts and a mouse cell line deficient in thymidine kinase. The following markers and syntenic groups were assigned: SOD1 to PPA3, GLO-ME1 to PPA-4, PGM2 to PPA5, CKBB-SORD to PPA7, LDHB to PPA11 and LDHA to PPA14. These localizations are in agreement wit hthe following homoeologies with the human karyotype: PPA3-HSA21, PPA4-HSA6, PPA5-HSA4, PPA7-HSA14 and 15, PPA11-HSA12, PPA14-HSA11.     

Mapping of bovine prolactin and rhodopsin genes in hybrid somatic cells

The genes encoding bovine prolactin and rhodopsin were assigned to syntenic groups on the basis of hybridization of DNA from a panel of bovine-hamster hybrid somatic cell lines with cloned prolactin and rhodopsin gene probes. Prolactin was found to be syntenic with previously mapped glyoxalase, BoLA and 21-hydroxylase genes, establishing a syntenic conservation with human chromosome 6. The presence of bovine rhodopsin sequences among the various hybrid cell lines was not concordant with any gene previously assigned to one of the 23 defined autosomal syntenic groups. Thus, rhodopsin marks a new bovine syntenic group, U24, leaving only five cattle autosomes unmarked by at least one biochemical or molecular marker.     

The rat vitamin D binding protein (Gc-globulin) gene is syntenic with the rat albumin and alpha-fetoprotein genes on chromosome 14

Using a panel of mouse X rat somatic cell hybrids and a characterized rat vitamin D binding protein (DBP) cDNA probe, we assigned the gene coding for rat DBP to chromosome 14. We conclude that the genes for DBP, albumin, and alpha-fetoprotein, all of which derive from a common precursor, are syntenic in the rat, as they are in man.     

The terminal deoxynucleotidyltransferase gene is located on human chromosome 10 (10q23----q24) and on mouse chromosome 19

Terminal deoxynucleotidyltransferase (TdT) is a DNA polymerase expressed in immature lymphocytes of the thymus and bone marrow, as well as certain leukemic cells. Chromosomal assignment of the gene coding for human TdT was accomplished by in situ hybridization of a 3H-labeled cDNA probe to human chromosome preparations and by Southern blot analysis of somatic cell hybrid DNAs. The human TdT gene was mapped to the region q23----q24 of chromosome 10. Breaks at this site have been reported in different translocations in human leukemias. The mouse TdT gene was assigned to chromosome 19 by Southern blot analysis of mouse X Chinese hamster somatic cell hybrids. This result adds a fourth locus to the conserved syntenic group on mouse chromosome 19 and human chromosome 10.     

Immunochemical evidence that the single lactate dehydrogenase of lampreys is more similar to LDHB4 than to LDHA4 of hagfish

The tetrameric lactate dehydrogenases (LDH) of vertebrates contain several different subunits that arose by gene duplication. While the A and B subunits occur in all classes of gnathostomes, the enzymes of agnathans appear to represent two stages in the evolution of vertebrate LDH. Lampreys of the family Petromyzontidae have a single enzyme classified as LDHA4, while hagfish possess both A and B subunits which form only the two homopolymers LDHA4 and LDHB4. It is generally assumed that the original vertebrate LDH was an A4 type, that duplication to give the B subunit occurred prior to the divergence of lampreys and hagfish, and that modern lampreys subsequently lost expression of the B gene. Lactate dehydrogenases were purified from representatives of all three lamprey families, and it was confirmed that members of the Mordaciidae and Geotriidae also possess single tetrameric LDH enzymes containing one subunit type. The kinetic properties of the lamprey LDH enzymes were compared with the LDH homopolymers of hagfish, skate, and sardine. These properties did not allow the lamprey enzymes to be unequivocally identified as either LDHA4 or LDHB4. Immunochemical titration using antisera against lamprey and hagfish LDH homopolymers demonstrated that the lamprey LDH enzymes showed greater immunochemical similarity to LDHB4 than to LDHA4 of hagfish. It is concluded that there is little evidence for the claim that the original vertebrate LDH was an A4 rather than B4 type.     

Chromosomal localization of human and rat A alpha, B beta, and gamma fibrinogen genes by in situ hybridization

In situ hybridization of radiolabeled fibrinogen cDNAs to human and rat metaphase chromosomes has shown that the genes encoding the A alpha, B beta, and gamma fibrinogen subunits are syntenic in both species. Our data localize the human fibrinogen gene cluster to band q31 on chromosome 4, thereby confirming and extending previous map assignments of these genes in man. We have also assigned these genes to the q31----q34 region of rat chromosome 2. This is the first map assignment of these genes in the rat and also the first report to clearly establish linkage of the B beta subunit gene to the A alpha and gamma genes in this species.