Identification of all pachytene bivalents in the common shrew using DAPI-staining of synaptonemal complex spreads

A major problem in studies of synaptonemal complexes (SC) is the difficulty in distinguishing individual chromosomes. This problem can be solved combining SC immunostaining with FISH of chromosome-specific sequences. However, this procedure is expensive, time-consuming and applicable only to a very limited number of species. In this paper we show how a combination of SC immunostaining and DAPI staining can allow identification of all chromosome arms in surface-spreads of the SC of the common shrew (Sorex araneus L.). Enhancement of brightness and contrast of the images with photo editing software allowed us to reveal clear DAPI-positive and negative bands with relative sizes and positions similar to DAPI landmarks on mitotic metaphase chromosomes. Using FISH with DNA probes prepared from chromosome arms m and n we demonstrated correct recognition of the chromosomes mp and hn on the basis of their DAPI pattern. We show that the approach we describe here may be applied to other species and can provide an important tool for identification of individual bivalents in pachytene surface-spreads. ^†Our co-author Eugene Perepelov died from an accident on 6 June 2006, much to our great shock and sadness. We dedicate this paper to his memory.     

Molecular evidence and high genetic diversity of shrew-borne Seewis virus in Slovenia

Seewis virus, the shrew-borne hantavirus from Sorex araneus, has been molecularly detected in reservoir hosts in many different central European countries and Russia. Slovenia is a known endemic country for rodent-borne hantaviruses, therefore the aim of the study was to investigate the presence of shrew-borne hantaviruses in insectivores. Viral L, S and M segment have been recovered only from tissue samples of 7 S. araneus, despite several shrew species were tested. Phylogenetic analysis showed high genetic diversity of SWSV in Slovenia, ranging from 3 to 19.4% for different viral segments. The most divergent were M segment sequences, with 19.4% nucleotide divergence among Slovenian strains. Above that, different SWSV strains from Slovenia do not group into separate geographic clusters. While three separate genetic clades were determined, two of them were simultaneously present in one location at the same time.     

Helminths of the vagrant shrew, <Emphasis Type="Italic">Sorex vagrans</Emphasis>, from western Montana,USA

A total of 19 helminth species (1 trematode, 11 cestodes, 7 nematodes) were collected from 45 vagrant shrews, Sorex vagrans (Mammalia, Soricidae), in western Montana, USA. One trematode (Brachylaima sp.), 2 cestodes (Paruterina candelabraria, Staphylocystoides longi), and 6 nematodes (Baruscapillaria rauschi, Eucoleus oesophagicola, Longistriata meylani, Paracrenosoma sp., Parastrongyloides winchesi, Pseudophysaloptera formosana) are reported for the first time from this host. Baruscapillaria rauschi n. comb. is proposed for Capillaria rauschi Read, 1949. This is the first record of merocercoids of P. candelabraria from a shrew, and the first report of the genus Paracrenosoma in North America.     

Unusual distribution pattern of telomeric repeats in the shrews <Emphasis Type="Italic">Sorex araneus</Emphasis> and <Emphasis Type="Italic">Sorex granarius</Emphasis>

Sorex araneus and Sorex granarius are sibling species within the Sorex araneus group with karyotypes composed of almost identical chromosome arms. S. granarius has a largely acrocentric karyotype, while, in S. araneus, various of these acrocentrics have combined together by Robertsonian (Rb) fusions to form metacentrics, with the numbers and types of metacentrics differing between chromosomal races. Our studies on telomeric sequences in S. araneus and S. granarius revealed differences between chromosomes and between species. In S. araneus (the Novosibirsk race), hybridization signals were present on the telomeres of all the chromosomes after FISH with a PCR-generated telomeric probe. In addition, hybridization signals were observed at high frequencies in the pericentric regions of some but not all metacentrics formed by Rb fusion. There were fewer signals on those metacentrics formed earlier in the evolution of S. araneus. This suggests that S. araneus chromosomes retain at least some telomeric repeats during Rb fusion, but that these repeats are lost or modified over time. These results are critical for the interpretation of the well-studied hybrid zones between chromosomal races of S. araneus, given that Rb fission has been postulated in such hybrid zones and that the likelihood of Rb fission will relate to presence/absence of telomeric sequences at the centromeres of metacentrics. In S. granarius, there were strong signals at the proximal (centromeric) telomeres of the acrocentrics after FISH with a DNA telomeric probe. FISH with a PNA telomeric probe on S. granarius acrocentrics showed that the proximal telomeres were 213 kb on average, while the length of the distal telomeres was 3.8 kb on average. Two-colour FISH, using a telomeric DNA probe and a microdissected probe generated from the pericentric regions of the S. granarius chromosomes a and b, revealed regions on distinct chromatin fibres where telomeric and microdissected probes were colocalized or localized sequentially. The proximal telomeres of S. granarius are highly unusual both in their large size and their heterogeneous structure relative to the telomeres of other mammals.     

Chromosomal locations of four minor rDNA loci and a marker microsatellite sequence in barley

Four minor rDNA loci have been mapped physically to barley (Hordeum vulgare L.) chromosomes 1 (7I), 2 (2I), 4 (4I), and 5 (1I) by a two-stepin situ hybridization procedure including a GAA microsatellite sequence. Reprobing with the microsatellite resulted in a distinct banding pattern, resembling the C-banding pattern, which enabled unequivocal chromosome identification. This study suggests that gene mapping accuracy may be improved by using probes with well-characterized and narrow hybridization sites as cytological markers which are situated close to the gene locus. One of the rDNA loci is located about 54% out on the short arm of chromosome 4 and it has not previously been reported in barley. We have disignated the new locusNor-16. rDNA loci on homoeologous group 4 chromosomes have not yet been reported in otherTriticeae species. The origin of these 4 minor rDNA loci is discussed in relation to their equilocal distribution on the chromosomes.     

Evolution of Genome Organizations of Squirrels (Sciuridae) Revealed by Cross-Species Chromosome Painting

With complete sets of chromosome-specific painting probes derived from flow-sorted chromosomes of human and grey squirrel (Sciurus carolinensis), the whole genome homologies between human and representatives of tree squirrels (Sciurus carolinensis, Callosciurus erythraeus), flying squirrels (Petaurista albiventer) and chipmunks (Tamias sibiricus) have been defined by cross-species chromosome painting. The results show that, unlike the highly rearranged karyotypes of mouse and rat, the karyotypes of squirrels are highly conserved. Two methods have been used to reconstruct the genome phylogeny of squirrels with the laboratory rabbit (Oryctolagus cuniculus) as the out-group: (1) phylogenetic analysis by parsimony using chromosomal characters identified by comparative cytogenetic approaches; (2) mapping the genome rearrangements onto recently published sequence-based molecular trees. Our chromosome painting results, in combination with molecular data, show that flying squirrels are phylogenetically close to New World tree squirrels. Chromosome painting and G-banding comparisons place chipmunks (Tamias sibiricus ), with a derived karyotype, outside the clade comprising tree and flying squirrels. The superorder Glires (orde Rodentia + order Lagomorpha) is firmly supported by two conserved syntenic associations between human chromosomes 1 and 10p homologues, and between 9 and 11 homologues.     

Chromosome length polymorphisms in a Septoria tritici population

Summary Transverse alternating field electrophoresis (TAFE) was used to compare the electrophoretic karyotypes of seven Septoria tritici isolates sampled from a single population. Isolates were selected based on differences at 12 DNA restriction fragment length polymorphism (RFLP) loci. Significant differences in electrophoretic karyotype existed among the isolates. Isolates had 14–16 bands, believed to correspond to chromosomes, ranging in size from approximately 330 to 3500 kb. Homologous chromosomes were identified by hybridization of anonymous single-locus and multiplelocus nuclear DNA sequences to Southern blots of TAFE gels. Length differences of up to 20% existed among homologous chromosomes. Densitometry and probe hybridization data showed that several bands contained two chromosomes. Probe pSTS192 hybridized to two chromosomes in each isolate, supporting previous data which suggested that this probe hybridized to two unlinked RFLP loci. Hybridization with probe pSTL53 provided additional evidence of partial diploidy at an RFLP locus in one isolate.     

Bone tissue resorption markers in metastatic involvement of the skeleton

Clinical significance of intermolecular relationships of bone matrix collagen pyridinoline and deoxypyridinoline in the urine is assessed in 137 cancer patients with metastases to the bones and 16 without metastatic involvement of the bone. Bone tissue resorption markers were studied by solid-phase extraction and high performance liquid chromatography and excretion was expressed as the ratio to urine creatinine. The levels of collagen pyridine bonds were significantly higher in cancer patients with metastases to bones than in patients without metastases and in control group consisting of 137 normal subjects. In addition, urine levels of pyridinoline and deoxypyridinoline in cancer patients without metastases to bones were significantly higher than in controls. A significant increase in urinary excretion of pyridine bonds was observed in bone involvement in patients with malignant tumors of different localization: breast, lungs, and prostate. The data indicate a possibility of using collagen pyridine bonds for early detection of metastatic destruction of the skeleton. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 3, pp. 323–328, March, 1998     

Electron-histochemical data on the localization of aminopeptidase M in the liver

The activity of aminopeptidase M in rat liver is studied electron histochemically. The enzyme is shown to be localized in the lysosomes of Kupffer's cells and endotheliocytes, and extracellularly on hepatocyte microvilli. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 312–314, September, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Immunohistochemical detection of the localization of melationin and N-acetylserotonin in enterochromaffin cells

Melatonin synthesis was identified by an immunohistochemical method with specific antisera against melatonin and N-acetylserotonin in the enterochromaffin cells of the gastrointestinal tract. It is considered that enterochromaffin cells, together with the pinealocytes of the pineal gland and other cells synthesizing melatonin in the retina and cerebellum, form a group of melatonin-producing cells with an important role in the maintenance of homeostasis.Laboratory of Histochemistry and Electron Microscopy, Department of Pathological Anatomy of Human Tumors, Oncological Scientific-Research Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Kraevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 11, pp. 1400–1401, November, 1976.     

Chromosome Sorting and PCR-Based Physical Mapping in Pea (Pisum Sativum L.)

Three pea lines with reconstructed karyotypes were used for analysis and subsequent purification of individual chromosome types using flow cytometry and sorting. The lines JI 145, JI 146, and JI 148 possess defined chromosomal translocations allowing discrimination of three to four chromosome types from each line based on the different sizes of translocation chromosomes. Whereas only two chromosomes could be sorted from standard (wild-type) karyotype, a combined use of these lines allowed sorting of six out of the seven types of pea chromosomes. Chromosomes were identified and purity of flow-sorted fractions was assessed using fluorescence in-situ hybridization with a PisTR-B probe that was previously shown to give labelling patterns characteristic for each chromosome types. The fractions of flow-sorted chromosomes were of very high purity (> 95%) and proved to be suitable for detection of gene and marker sequences using PCR with specific primers. Three fractions containing chromosomes 2⁷, 7² and a pool of all remaining chromosomes (1, 3, 4, 5, 6) flow-sorted from the line JI 148 were then used for PCR-based physical localization of genetic markers selected from linkage groups IV and VII. These experiments enabled assignment of the linkage groups IV and VII to chromosomes 4 and 7, respectively.     

The chromosome complement ofAcomys spp. (Rodentia,Muridae) from Oursi,Burkina Faso—the ancestral karyotype of thecahirinus-dimidiatus group?

We present here data on chromosome banding analysis (R- and C-bands) ofAcomys sp. (Rodentia, Muridae) from Oursi, Burkina Faso, characterized by 2n=FN=68 and comparison of its banding patterns with those ofAcomys dimidiatus from Saudi Arabia (2n=38, FN=70), studied previously. The study revealed complete homology between acrocentric chromosomes ofAcomys sp. and chromosome arms of 16 pairs of metacentric and two pairs of acrocentric chromosomes ofA. dimidiatus. In addition to monobrachial homology, one tandem translocation accompanied by a centromeric shift was identified in the karyotype of the latter species. The data obtained show that karyotypes of all the species of theAcomys cahirinus-dimidiatus group studied previously may be derived from that ofAcomys sp. from Oursi by means of numerous non-homologous Rb translocations and 1–2 tandem translocations, and thus its karyotype may be considered as ancestral for thecahirinus-dimidiatus group.accepted for publication by M. Schmid     

Electron-histochemical localization of liver collagenase

Localization of collagenase in normal rat liver is studied by the electron-histochemical method. Enzyme activity is detected in Kupffer and endothelial cells and on hepatocyte microvilli. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp. 98–100, January, 1996 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Electrophoretic karyotype of Mucor circinelloides

Contour-clamped homogeneous electric field (CHEF) gel electrophoresis was used to separate chromosomal size DNA molecules of two Mucor circinelloides strains. Electrophoretic karyotypes revealed the presence of eight distinct bands for the M. circinelloides f. lusitanicus strain, and four, presumably multiple, bands for the M. circinelloides f. gryseo-cyanus strain. The approximate sizes of the resolved chromosomal DNA bands ranged from 2.3 to 8.1 Mb, giving estimated genome sizes of 38.7 and 32.6 Mb, respectively. Hybridisation techniques were used to assign the leuA gene to a chromosome.     

DNA translocations contribute to chromosome length polymorphisms in Candida albicans

Summary Rotating-gel electrophoresis and DNA hybridization were used to compare the electrophoretic karyotype of six Candida albicans isolates. The hybridization pattern for 22 cloned sequences, including eight previously unmapped genes, indicates that there are eight pair of homologous chromosomes in each strain. However, since homologous chromosomes can differ in length, it is possible to resolve more than eight bands in some strains. The mapping data demonstrate that linkage groups are generally conserved suggesting that, in spite of gross karyotype differences, there is an underlying similarity in the genome organization of different isolates. The hybridization data also provide direct evidence that DNA translocations and reciprocal translocations contribute to chromosome length polymorphisms in C. albicans.     

Gene assignment in Ateles paniscus chamek (Platyrrhini, Primates). Allocation of 18 markers of human syntenic groups 1, 2, 7, 14, 15, 17 and 22

Eighteen markers allocated to human syntenic groups 1, 2, 7, 14, 15, 17 and 22 were assigned to the chromosome complement of the neotropical primate Ateles paniscus chamek. These new allocations and existing gene charts in this species were compared with chromosome painting patterns produced by human chromosome probes in the congeneric species Ateles geoffroyi and with available data on the human genome and gene mapping. These comparisons showed congruent findings in Ateles and provided good evidence of how several human syntenic groups were evolutionarily rearranged. This revised version was published online in July 2006 with corrections to the Cover Date.     

Chromosome mapping ofSoa,a gene influencing gustatory sensitivity to sucrose octaacetate in mice

Strain distribution patterns among recombinant inbred strains suggested that a locus influencing taste sensitivity to sucrose octaacetate was on chromosome 6. A location forSoa was established by linkage analysis of behavioral and electrophoretic data from outbred and congenic strains and from test-cross progeny. Haplotyping of 41 outbred CFW-Cr animals with a cDNA probe showed perfect cosegregation ofSoa andPrp, a gene for salivary proline-rich proteins. Five of twelve B6. SW-Soa ^a strains were found to retainLdr-1, lactate dehydrogenase regulator-1, on chromosome 6 as an allelic passenger from the SWR/J donor strain (source of theSoa ^a Taster allele). Centimorgan distance was estimated using the ABP/Le linkage-testing strain (non-Taster,Soa ^b) and the SWR/J strain (Taster,Soa ^a) in a testcross breeding system. The data are consistent with a position for theSoa locus on mouse chromosome 6, 62 cM from the centromere.This research was supported in part by Grants DC00150 (G. W.) and DE003658 (E.A.A.). This paper is based on a thesis submitted to the Florida State University by the first author in partial fulfillment of the requirements for the Master of Sciences degree.     

Immunocytochemical study of the localization of scavenger receptor in human aortic smooth-muscle cells

Scavenger receptor was soughtin situ in human aortic smooth-muscle cells and in a primary culture of intact human aortic intima using antibodies to scavenger receptor. For identification of smooth-muscle cells, double staining making use of antibodies to murine α-actin was used. The presence of scavenger receptor in smooth-muscle cells of the intima and media of human aorta was demonstrated on aortic slices. In cultured smooth-muscle cells from normal human aortic intima scavenger receptor was distributed over the entire surface of the cell membrane, forming clusters in some places. These results suggest that human aortic smooth-muscle cells express scavenger receptor. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 195–198, August, 1995 Presented by V. N. Smirnov, Member of the Russian Academy of Medical Sciences