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The mode of inheritance of supernumerary segments located on three different chromosome pairs was investigated in controlled crosses with specimens of the grasshopper Chorthippus jacobsi. While extra segments located on chromosomes M5 and M6 showed Mendelian inheritance, that on S8 did not. Thus, the two supernumerary heterochromatic chromosome segments located distally on the S8 chromosome accumulated through non-Mendelian transmission through both sexes. The observed transmission patterns may be explained by gametic selection for spermatozoa carrying segmented S8 chromosomes, in addition to meiotic drive for segmented S8 chromosomes in heterozygous females. The significance of these findings for the maintenance of these polymorphisms in natural populations is discussed.by S.A. Gerbi 相似文献
3.
M. Bakkali J. Cabrero M. D. López-León F. Perfectti J. P. M. Camacho 《Protoplasma》2001,217(4):185-190
Summary Fluorescence in situ hybridization revealed the presence of ribosomal RNA genes in paracentromeric regions of all A chromosomes and in the distal half of B chromosomes in embryonic cells from Moroccan specimens of the grasshopperEyprepocnemis plorans. The expression of these genes was monitored by the presence of nucleoli attached to each chromosome bivalent in diplotene cells from males collected from two different Moroccan populations and was compared to previous data of Spanish populations. Whereas only the nucleolus organizer regions (NORs) on S9–S11 and X chromosomes were active in the Spanish specimens. Moroccan individuals showed NOR activity in all chromosomes. The rRNA genes on the B chromosome were inactive in both populations. The S9 and S10 NORs were less active in Moroccan specimens than in Spanish specimen, which might be partly explained by the negative interdependence for expression of the S10 NOR with respect to those on L2 and X chromosomes. On the other hand, the X NOR was more active in Moroccan specimens than in Spanish specimens, and this might be partly due to the positive effect that the presence of B chromosomes has on the expression of this NOR. The implications of these observations on current models of NOR activity regulation are discussed.Abbreviation NOR
nucleolus organizer region 相似文献
4.
A. Shahla T. Tsuchiya 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,75(1):5-12
Summary Genetic and cytogenetic techniques were applied to linkage analysis of chromosome 1. Eight marker genes, including five on the short arm and three on the long arm, were analyzed with two telotrisomic lines, Triplo 1S and 1L, and one acrotrisomic line, Triplo 1L1S. Telotrisomic analysis confirmed the position of a
c
2, gs3, f3, br, f5, and f8 on the short arm, and 1k2 and n on the long arm of the linkage map of chromosome 1. Conventional three-point tests with two triple genetic marker stocks showed that f
c
is located between br and gs3, and n is located in the middle of f8 and 1k2. Acrotrisomic for 1L1S was used for cytogenetic linkage mapping. Giemsa N-banding technique showed that the long (1L) and short (1S) arm had deficiencies of 37.5% and 73%, respectively. Genes f5, br, f
c, gs3 and f8 in 1S and 1k2 in 1L were located in the deficient segments of 1L1S. A trisomic ratio obtained with n indicated an association of this gene with the long arm of the acrocentric chromosome. Cytological behavior, morphological characteristics, fertility, and transmission in the acrotrisomic 1L1S are also reported.Contribution from Department of Agronomy and published with the approval of the Director of Colorado State University Agricultural Experiment Station. Series No. 2984. Supported by USDA Competitive Research Grant No. 82-CRCR-1-1020, USDA-CSU Cooperative Research Grant No. 58-9AHZ-2-265 and Colorado State University Hatch project 相似文献
5.
L. Serrano C. García de la Vega J. L. Bella C. Lpez-Fernndez G. M. Hewitt J. Goslvez 《Journal of evolutionary biology》1996,9(2):173-184
Two grasshopper subspecies, Chorthippus parallelus parallelus (Cpp) and Chorthippus parallelus erythropus (Cpe), meet along the Pyrenees where they hybridize and produce a hybrid zone. A contact zone located in the Col de Portalet has been analyzed for the distribution of chromosome markers on the sex (X) chromosome in pure and hybrid populations. C-banding allowed us to distinguish both pure subspecific forms and recombinant forms, and to demonstrate their different frequencies through the contact zone. Interestingly, the distal C-band (P) on the X chromosome that characterizes Cpp individuals occurs at very high frequency through the zone and then drops sharply, close to where pure Cpe populations are found. A novel interstitial C-band (H) has been found, probably derived from that characterizing Cpe individuals (E). This marker band is only present in hybrid populations. These data are discussed in the light of the dynamics of the hybrid zone. 相似文献
6.
The endemic Australian grasshopper Heteropternis obscurella shows considerable variation in respect of both chromosome structure and chromosome behaviour. The structural differences depend upon different patterns of heterochromatin distribution as revealed by C-banding. These involve differences between populations in respect of polytypic variation in the size of paracentromeric C-bands and differences within populations in respect of polymorphisms both for terminal blocks of heterochromatin in autosomes 3 to 8 and a large proximal block of heterochromatin in autosome 7. The behavioural differences stem in part from genotypically determined variation in the chiasma distribution pattern which is markedly localised in a majority of populations but more randomly distributed in populations from the south of Western Australia. Behavioural differences also arise as secondary consequences of the presence of those heterochromatic blocks which occur as polymorphisms. The distal blocks on autosomes 5, 6, 7 and 8 lead to a redistribution of chiasmata to more proximal sites while the proximal block on 7 leads to the virtual abolition of chiasma formation in that bivalent and its replacement by a non-chiasmate mechanism of segregation. This depends upon a persistent proximal heterochromatic association between the pairing partners. The presence of distal C-blocks on bivalents 3 to 8 gives rise to persistent pseudomultiples, formed as a result of heterochromatic associations between these blocks. Such pseudomultiples involve any two or three of these six bivalents, provided they carry distal blocks, and their frequency rises dramatically in the presence of the proximal heterochromatic block on chromosome 7. 相似文献
7.
A cytogenetic analysis in Psophus stridulus (L.) (Orthoptera: Acrididae): B-chromosomes and abnormal spermatid nuclei 总被引:1,自引:1,他引:0
The male chromosome complement of Psophus stridulus (L.) (Orthoptera: Acrididae) has been analyzed by using orcein staining, C-banding and silver impregnation. During spermatogenesis only one pair of autosomes (M9) shows an active nucleolar organizer region located in a C-banded constriction. There are other chromosome pairs with constrictions but these do not show nucleolar activity. The relationship between these constrictions and the C-banding pattern exhibited by this species is analyzed.In a sample of 83 males from five populations, two different supernumerary chromosomes were observed. Four males had a metacentric B-chromosome (Bm) similar in size to the sex chromosome and mitotically stable. Its meiotic behaviour indicates that it is an isochromosome. An additional small B-chromosome (B8) was also found in a single follicle of one individual carrying the Bm.A high rate of abnormal spermatids (macrospermatids) was scored in the individuals carrying B's. This proportion is notably higher in the follicle containing both the Bm and the B8. 相似文献
8.
N. V. Trubacheeva T. T. Efremova E. D. Badaeva L. A. Kravtsova L. I. Belova E. P. Devyatkina L. A. Pershina 《Russian Journal of Genetics》2009,45(12):1438-1443
Alloplasmic lines of common wheat with disomic substitution of chromosome 7D for telocentric chromosome 7H1Lmar of barley H. marinum subsp. gussoneanum Hudson were isolated from the plants of generation BC3, produced as a result of backcrossing of barley-wheat hybrids H. marinum subsp. gussoneanum (2n = 28) × T. aestivum (2n = 42), Pyrotrix, cultivar, with 28 common wheat cultivars Pyrotrix 28 and Novosibirskaya 67. Chromosome substitution pattern
was determined using SSR analysis and C-banding. In preliminary genomic in situ hybridization experiments, telocentric chromosomes
were assigned to wild barley was established. In the BC3F8 generations of three alloplasmic lines with the 7H1Lmar(7D) substitution type the differences in fertility manifestation were observed: most of the L-32(1) plants were sterile,
in line L-32(2) only sporadic plants were sterile, and line L-32(3) was fertile. Simultaneously with these experiments, using
selfpollinated progeny of the hybrids obtained in crosses of common wheat cultivar Saratovskaya 29 (2n = 41), monosomic for chromosome 7D, with common wheat cultivar Pyrotrix 28 with addition of pair of telocentric chromosomes
7H1Lmar (7D) of barley H. marinum subsp. gussoneanum, euplasmic wheat-barley ditelosomic substitution 7H1Lmar (7D) lines were isolated. The lines obtained had normal fertility. PCR analysis of the 18S/5S mitochondrial repeat (hereafter,
mtDNA sequence) in alloplasmic and euplasmic ditelosomic substitution lines 7H1Lmar(7D) was performed. In the plants from alloplasmic sterile line L-32(1), the sequences only of the barley (maternal) type
were revealed, while the plants from alloplasmic fertile lines L-32(2) and L-32(3) demonstrated heteroplasmy (the presence
of barley- and wheat-like sequences within one individual). In euplasmic ditelosomic substitution lines the presence of only
wheat-like 18S/5S mitochondrial repeat sequences was observed. The results indicate that the presence of barley-like mtDNA
sequences in alloplasmic substitution lines was not associated with the presence of barley chromosomes in their nuclear genomes. 相似文献
9.
《Journal of bryology》2013,35(2):303-314
AbstractExtensive cytological variation between British populations of Pellia endiviifolia (Dicks.) Dum. (n = 8+x/y) permits the recognition of six distinct karyotypes; one of them found also in Greece and another in the U.S.S.R. Although based on typically small amounts of constitutive heterochromatin, Giemsa C-banding patterns serve to identify each of three chromosomes, 1, 6 and 9, as dimorphic or polymorphic. Relative proportions of chromosomes differ between karyotypes and further variation relates toa nucleolar organiser region (NOR) on chromosome 6 of one population in addition to the NOR generally located in chromosome 7. These findings have repercussions intaxonomy and reproductive behaviour that are discussed in detail. 相似文献
10.
In this study, two species of Romaleidae grasshoppers, Radacridium mariajoseae and R.nordestinum, were analyzed after CMA3/DA/DAPI sequential staining and fluorescence in situ hybridization (FISH) to determine the location of the 18S and 5S rDNA and histone H4 genes. Both species presented karyotypes composed of 2n = 23, X0 with exclusively acrocentric chromosomes. CMA3+ blocks were detected after CMA3/DA/DAPI staining in only one medium size autosome bivalent and in the X chromosome in R. mariajoseae. On the other hand, all chromosomes, except the L1 bivalent, of R. nordestinum presented CMA3+ blocks. FISH analysis showed that the 18S genes are restricted to the X chromosome in R. mariajoseae, whereas these genes were located in the L2, S9 and S10 autosomes in R. nordestinum. In R. mariajoseae, the 5S rDNA sites were localized in the in L1 and L2 bivalents and in the X chromosome. In R. nordestinum, the 5S genes were located in the L2, L3, M4 and M5 pairs. In both species the histone H4 genes were present in a medium size bivalent. Together, these data evidence a great variability of chromosome markers and show that the 18S and 5S ribosomal genes are dispersed in the Radacridium genome without a significant correlation. 相似文献
11.
Standard karyotype of Triticum searsii and its relationship with other S-genome species and common wheat 总被引:1,自引:0,他引:1
B. Friebe N. A. Tuleen B. S. Gill 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(2):248-254
C-banding polymorphism was analyzed in 14 accessions of Triticum searsii from Israel, and a generalized idiogram of the species was established. One accession was homozygous for whole arm translocations T1SsS·4SsS and T1SsL·4SsL. C-banding analysis was also used to identify 7 T. aestivum cv Chinese Spring-T. searsii disomic chromosome addition lines, 14 ditelosomic chromosome addition lines, 21 disomic whole chromosome, and 31 ditelosomic chromosome substitution lines. The identity of these lines was further confirmed by meiotic pairing analysis. Sporophytic and gametophytic compensation tests were used to determine the homoeologous relationships of the T. searsii chromosomes. The results show that the T. searsii chromosomes do not compensate well for their wheat homoeologues. The C-banding patterns of T. searsii chromosomes are distinct from those of other S-genome species and from the B-genome chromosomes of wheat, indicating that T. searsii is not a direct B-genome donor species of T. turgidum and T. aestivum.Contribution No. 95-72-J from the Kansas Agricultural Experiment Station, Kansas State University, Manhattan, Kansas, USA 相似文献
12.
Identification of Haynaldia villosa chromosomes added to wheat using a sequential C-banding and genomic in situ hybridization technique 总被引:4,自引:0,他引:4
S. B. Zhong D. Y. Zhang H. B. Li J. X. Yao 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(1):116-120
Genomic in situ hybridization (GISH) offers a convenient and effective method for cytological detection, but can not determine the identity of the chromosomes involved. We integrated C-banding with GISH to identify Haynaldia villosa chromosomes in a wheat background. All chromosomes of H. villosa showed C-bands, either in telomeric regions or in both telomeric and centromeric regions, which allowed unequivocal identification of each H. villosa chromosome. The seven pairs of H. villosa chromosomes were differentiated as 1–7 according to their characteristic C-bands. Using a sequential C-banding and GISH technique, we have analyzed somatic cells of F3 plants from the amphiploid Triticum aestivum-H. villosa x Yangmai 158 hybrids. Three plants (94009/5-4,94009/5-8 and 94009/5-9) were shown to contain H. villosa chromosome(s). 94009/5-4 (2n = 45) had three H. villosa chromosomes (2, 3 and 4); 94009/5-8 (2n = 45) possessed one chromosome 4 and a pair of chromosome 5, and 94009/5-9 (2n = 43) was found to have one chromosome 6 of H. villosa. The combination of GISH with C-banding described here provides a direct comparison of the cytological and molecular landmarks. Such a technique is particularly useful for identifying and localizing alien chromatin and DNA sequences in plants. 相似文献
13.
Spontaneous chromosome mutations in Truxaline grasshoppers 总被引:2,自引:0,他引:2
David I. Southern 《Chromosoma》1967,22(3):241-257
Three distinct mutant conditions are described in single male individuals from three species of short horn grasshopper. Of these, one is an entire germ line mutant of Myrmeleotettix maculatus, heterozygous for a centric fusion between single M4 and M5 telocentric chromosomes. In contrast, the remaining two mutants are present in mosaic form. One is heterozygous for an L1-M4 interchange in Omocestus viridulus, the other tetrasomic for the M4 chromosome in Chorthippus parallelus which in addition is characterised by the inclusion of a supernumerary heterochromatic segment on one S8 homologue. Centric fusion in Myrmehotettix maculatus has neither disturbed the chiasma potential of the elements constituting the fusion multiple nor, has it apparently influenced the production of balanced gametes. The pattern of chiasma formation in the L1-M4 interchange multiple lends support to the contention that the process of chiasma formation originates near the distal end of chromosome arms in Omocestus viridulus. There is no interaction between the two mutant conditions of tetrasomy and the presence of supernumerary segments in Chorthippus parallelus. Moreover, because of the precocious nature of two of the four M4 homologues there is little tendency to form multivalents. The two M4 bivalents share a similar mean chiasma frequency. 相似文献
14.
T. Tsuchiya R. J. Singh Azizeh Shahla A. Hang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1984,68(5):433-439
Summary Three acrotrisomic lines, Triplo IL1S, 3L3S, and 4L4S, each carrying an extra acrocentric chromosome, were used for cytogenetic linkage mapping of barley chromosomes. The cytological structures of the acrocentric chromosome of the three acrotrisomic lines were studied with an improved Giemsa N-banding technique. The long (1L) and short arm (1S) of chromosome 1 had deficiencies of approximately 38% and 65%, respectively. The percentages of deficiencies were 0 and 77.8% for 3L and 3S, and 31.7 and 59.3% for 4L and 4S, respectively. All three genes tested (br, f
c
, gs3) in 1S and all three genes tested, f8, n and 1k2 in 1L showed a disomic ratio indicating that they are located in the deficient segments. Two genes (a
c
, yst2) located in the middle segment of 3S in linkage map showed a trisomic ratio, and two others a
n
, x
s
showed a disomic ratio. The only gene(f9) tested in 4L showed a trisomic ratio. Two genes (1g4, g1) located in the proximal segment of 4S in the linkage map showed a trisomic ratio, whereas two genes (br2, g13) located distally in 4S showed a disomic ratio, indicating that the breakage occurred between g1 and br2. This experiment demonstrates a new method for physical localization of genes on chromosome segments in material such as barley in which pachytene analysis can not be effectively used for accurate determination of break points in structural changes. Problems associated with this new technique are discussed.Contribution from the Department of Agronomy and published with the approval of the Director of Colorado State University Experiment Station as Scientific Series Paper No. 2823. Supported by USDA/SEA Competitive Research Grant Nos. 5901-0410-9-0334-0 and 82-CRCR-1-1020 and USDA-CSU Cooperative Research Grant 58-9AHZ-2-265 相似文献
15.
Four populations of Astyanax scabripinnis (Pisces, Characidae) were analyzed for B chromosome features. This species contains a metacentric macrochromosome (BM), similar in size to the first chromosome of the karyotype, besides two variant forms, a large submetacentric (BSM) and a small metacentric (Bm), both showing a reduced frequency. These variant forms were observed only in the populations from the Campos do Jordão region (São Paulo State, Brazil), although not present in all the populations sampled. The three B chromosome forms are heterochromatic and at least the BM and BSM are also GC-rich, as evidenced by C-banding and chromomycin A3 staining. In spite of the morphological similarity between the BM form and the first chromosome pair, they differ in the G-banding pattern, which does not favor a possible relationship among these chromosomes. FISH with a telomeric DNA probe evidenced signals on the terminal region of all chromosomes, including the Bs. Interstitial telomeric bands, indicative of some chromosomal rearrangements such as translocation or tandem fusion in the origin of the B chromosomes, were not observed. BSM and Bm are probable derivative B chromosome forms from an ancestral BM chromosome, showing a restricted occurrence and low frequency in the populations. 相似文献
16.
Sand perch Diplectrum formosum were collected in the Atlantic Ocean waters off the south‐eastern U.S. for life history analyses between April 2001 and July 2004 and ranged in size from 63 to 236 mm standard length (LS) and 0–8 years of age. Diplectrum formosum are simultaneous hermaphrodites that reach 50% sexual maturity at 12·2 months and 122·8 mm LS for testicular tissue and 13·6 months and 129·3 mm LS for ovarian tissue. The gonad contains ovarian and testicular tissue separated by a thin basement membrane, with no means of internal self‐fertilization. Spawning females were found between March and January with a peak of spawning activity in May and a realized spawning periodicity of 2 days, equivalent to a maximum of 168 spawning events per year. Fish with testicular tissue in spawning condition were obtained throughout the year in every month sampled with a maximum frequency between June and September. There were also trends indicating that testicular tissue was more likely to be in spawning condition in the presence of hydrated oocytes within the accessory structure. This may indicate the use of the accessory structure as a storage site for hydrated oocytes until a mate can be located. 相似文献
17.
Dietary analysis of the herbivorous hemiramphid Hyporhamphus regularis ardelio: an isotopic approach
The stable isotope values for a range of size classes of Hyporhamphus regularis ardelio from Moreton Bay, south‐east Australia were determined. There was a positive linear relationship between δ13C and standard length (LS)(δ13C = 0·034 LS ? 16·23; r2 = 0·78). δ13C ranged from ?8·48 to ?17·29‰ with the smallest size class (50 mm LS) being on average 1·04‰ enriched with respect to that of zooplankton (Temora turbinata) and 7·97‰ depleted compared to Zostera capricorni. δ13C was positively correlated with LS(P < 0·01)(more enriched with increasing LS) with those fish of the largest size class (225 mm LS) being 9·86 and 0·84‰ enriched than T. turbinata and Z. capricorni, respectively. There was no detectable trend in δ15N values with LS(P > 0·01) with δ15N, ranging from 9·18 to 11·00‰. Fish of all size classes were on average 2·32 and 7·63‰ more enriched than zooplankton and seagrass, respectively. Carbon isotope data indicate that H. r. ardelio commence life as carnivores and change to a diet in which seagrass is the primary carbon source. The dependence on animal matter, however, is always present. Due to the low percentage of nitrogen in Z. capricorni(2·5%) compared to zooplankton (9·1%) it appears that nitrogen from zooplankton is necessary throughout their life history with the carbon requirements for these fish coming chiefly from Z. capricorni. 相似文献
18.
Anadromous trout Salmo trutta exhibits sexual size dimorphism (SSD); females were larger than males in populations where male mean total length (LT) at maturity was below 49 cm and females were smaller than males when mean male LT was above 49 cm, the slope of the regression of female on male LT was 0·59. In streams with mean annual discharge below 41 m3 s?1, flow added significantly to a model with SSD as the dependent variable and male mean LT at maturity as the first predictor variable. There was a slight increase in SSD with increasing latitude, which may result from an increase in male size with increasing latitude. 相似文献
19.
A centric shift in the S11 chromosome of Aiolopus strepens, previously described as a pericentric inversion (Cabrero & Camacho, 1982), was analyzed by using the C-banding procedure. The location of breakage points as well as the posibilities of pericentric inversion and three-break transposition are discussed. The relationship between C-bands and NOR location as revealed by both silver staining and a double procedure Ag-NOR C-banding is also discussed. 相似文献
20.
Schindleria elongata,a new species of paedomorphic gobioid from the Red Sea (Teleostei: Schindleriidae)
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A new species of paedomorphic gobioid, Schindleria elongata, from the Red Sea, is described on the basis of five specimens. The new species is characterized by its lack of body pigmentation; the body depth at pectoral‐fin origin 4–5% of standard length (LS) and at anal‐fin origin 5–7% LS; the predorsal length 66–70% LS; pre‐anal length 66–71% LS; dorsal‐fin rays 13 or 14; anal‐fin rays 10 or 11; first dorsal‐fin ray at myomere 20 or 21; first anal‐fin ray below second to fourth dorsal‐fin rays; myomeres 19 or 20 + 13 or 14 = 33 or 34 total; premaxillae and dentaries with small teeth; gas bladder located posteriorly at 56–60% LS; males with a rod‐like, flexible urogenital papilla lacking lobes, projections or accessory papillae, with distal half tapering to a broad, angular point and usually posteriorly directed. A key to the species of Schindleriidae is presented. 相似文献