Immunofluorescent analysis of meiotic recombination in the domestic cat

The paper presents the analysis of the frequency, density, and distribution of recombination sites in the male meiosis of the domestic cat (Felis silvestris catus). The study was carried out using immunofluorescent staining of synaptonemal complex (SC) proteins, centromeric proteins and mismatch repair protein MLH1, a reliable marker of crossingover sites. We mapped 2633 sites of crossing over in 1098 individual autosomes. Based on these data, we estimated the total length of the genetic map of the domestic cat to be 2176 centimorgans. Positive correlation between the length of SC and the number of recombination sites common for mammalians was also found in the domestic cat. It was shown that this species was characterized by the highest density of recombination and the lowest interference in mammals.     

Mapping of the silver fox genes: assignments of the genes for ME1, ADK, PP, PEPA, GSR, MPI, and GOT1

Evidence is presented for the assignment of seven fox genes on the basis of the segregation data for chromosomes and enzymes of fox x Chinese hamster somatic cell hybrids. The chromosomal loci of the following enzyme genes were determined: ME1, VFU1; ADK and PP, VFU4; PEPA, VFU5; GSR, VFU7; and MPI and GOT1, VFU15. The localization of these genes now extends the fox genetic map to 22 mapped genes. Based on comparative analysis of mammalian genetic maps, karyotype evolution in Carnivora is discussed.     

Expression of human growth hormone in cultured mouse fibroblasts

The new system for the transfer and expression of foreign genes based on retroviral vectors pPS-neo, conferring neomycin resistance was constructed. The BALB/c mouse cell lines producing highly active human growth hormone (more than 7 micrograms/ml into culture medium) were constructed using these vectors. An antibody column was used to purify the growth hormone from cell culture medium. Possibilities of producers to be applied for gene therapy are discussed.     

Localization of the α2-macroglobulin gene and Lpm gene family on mink chromosome 9

Summary Using cloned cDNA for human ₂-macroglobulin (A2M) as a probe, mink-Chinese hamster hybrid cells were analysed. The results allowed us to assign a gene for A2M to mink chromosome 9. Breeding tests demonstrated that the Lpm-locus coding for other related -macroglobulin protein and the gene for peptidase B (PEPB) are linked 11±3 cm apart. The PEPB gene is located on mink chromosome 9, and hence, the Lpw-locus is on the same mink chromosome. The relationship of the genetic systems controlling the isotypically different -macroglobulins in mink serum are discussed.     

Regional assignment of the genes for TK1, GALK, ALDC, and ESD on chromosome 8 in the American mink by chromosome-mediated gene transfer

Summary A panel of clones of mink-Chinese hamster somatic cell hybrids was analysed to obtain data for assigning the genes for thymidine kinase-1 (TK1), galactokinase (GALK), subunit C of aldolase (ALDC), and esterase D (ESD) to specific mink chromosomes. The results demonstrate that the genes for TK1, GALK, ALDC and ESD are syntenic and located on mink chromosome 8. Prometaphase analysis of transformed mouse cells obtained by transfer of mink genes by means of metaphase chromosomes demonstrated the presence of mink chromosome 8 fragments of different sizes in some of the independent transformants. Segregation analysis of these fragments and mink TK1, GALK, ALDC and ESD allowed us to assign the genes for TK1 and GALK to 8p24, ALDC to pter-8p25, and ESD to 8q24-8qter.     

Putative promoter region of rRNA operon from archaebacterium Halobacterium halobium.

The 100 bp sequence from the beginning of the 16S rRNA gene of archaebacterium Halobacterium halobium and the adjacent 800 bp upstream sequence were determined. Four long (80 bp) direct repeats were found in the region preceeding the structural gene of the 16S rRNA. These repeats are proposed to constitute the promoter region of the rRNA operon of H. halobium.     

Nucleotide sequence of the Yersinia pestis gene encoding F1 antigen and the primary structure of the protein. Putative T and B cell epitopes.

The plasmid-located gene caf1 encoding the capsular antigen fraction 1 (F1) of Yersinia pestis was cloned and sequenced. The gene codes for a 170 amino acid peptide with a deduced Mr of 17.6 kDa. The signal peptide sequence was highly homologous to the E. coli consensus signal sequence. The F1 was assumed to have beta-sheet structure for the most part. The region located between amino acids 100 and 150 was suggested to contain putative antigenic determinants and to stimulate T cells.     

The structure of the yeast ribosomal RNA genes. I. The complete nucleotide sequence of the 18S ribosomal RNA gene from Saccharomyces cerevisiae.

The cloned 18 S ribosomal RNA gene from Saccharomyces cerevisiae have been sequenced, using the Maxam-Gilbert procedure. From this data the complete sequence of 1789 nucleotides of the 18 S RNA was deduced. Extensive homology with many eucaryotic as well as E. coli ribosomal small subunit rRNA (S-rRNA) has been observed in the 3'-end region of the rRNA molecule. Comparison of the yeast 18 S rRNA sequences with partial sequence data, available for rRNAs of the other eucaryotes provides strong evidence that a substantial portion of the 18 S RNA sequence has been conserved in evolution.     

Interaction of ATP with sarcoplasmic reticulum Ca2+-ATPase; effect on the conformational state of the enzyme

It was studied how temperature influences the NBD-Cl inactivation of sarcoplasmic reticulum Ca2+-ATPase and the protective effect of ATP under conditions preventing ATP hydrolysis. Two types of ATP-binding sites with Kd equal to 30 and 220 microM at 37 degrees C were found. ADP interacts with these sites with the (K'd = 20 and 200 microM). The temperature decrease from 25 degrees to 5 degrees C induces the abrupt increase in the Kd for the low affinity site. The possible reasons for heterogeneity of ATP-binding sites are discussed. The conclusion is made that interaction of monomers in oligomeric complex of Ca2+-ATPase induces heterogeneity of ATP-binding sites.