共查询到20条相似文献,搜索用时 437 毫秒
1.
Ehrmann IE; Ellis PS; Mazeyrat S; Duthie S; Brockdorff N; Mattei MG; Gavin MA; Affara NA; Brown GM; Simpson E; Mitchell MJ; Scott DM 《Human molecular genetics》1998,7(11):1725-1737
The Delta Sxrb interval of the mouse Y chromosome is critical for
spermatogenesis and expression of the male-specific minor transplantation
antigen H-Y. Several genes have been mapped to this interval and each has a
homologue on the X chromosome. Four, Zfy1 , Zfy2 , Ube1y and Dffry , are
expressed specifically in the testis and their X homologues are not
transcribed from the inactive X chromosome. A further two, Smcy and Uty ,
are ubiquitously expressed and their X homologues escape X-inactivation.
Here we report the identification of another gene from this region of the
mouse Y chromosome. It encodes the highly conserved eukaryotic translation
initiation factor eIF-2gamma. In the mouse this gene is ubiquitously
expressed, has an X chromosome homologue which maps close to Dmd and
escapes X-inactivation. The coding regions of the X and Y genes show 86%
nucleotide identity and encode putative products with 98% amino acid
identity. In humans, the eIF-2gamma structural gene is located on the X
chromosome at Xp21 and this also escapes X-inactivation. However, there is
no evidence of a Y copy of this gene in humans. We have identified
autosomal retroposons of eIF-2gamma in both humans and mice and an
additional retroposon on the X chromosome in some mouse strains. Ark blot
analysis of eutherian and metatherian genomic DNA indicates that X-Y
homologues are present in all species tested except simian primates and
kangaroo and that retroposons are common to a wide range of mammals. These
results shed light on the evolution of X-Y homologous genes.
相似文献
2.
3.
4.
5.
X chromosome inactivation (XCI) achieves dosage compensation between males and females for most X-linked genes in eutherian
mammals. It is a whole-chromosome effect under the control of the XIST locus, although some genes escape inactivation. Marsupial XCI differs from the eutherian process, implying fundamental changes
in the XCI mechanism during the evolution of the two lineages. There is no direct evidence for the existence of a marsupial
XIST homologue. XCI has been studied for only a handful of genes in any marsupial, and none in the model kangaroo Macropus eugenii (the tammar wallaby). We have therefore studied the sequence, location and activity of a gene SLC16A2 (solute carrier, family 16, class A, member 2) that flanks XIST on the human and mouse X chromosomes. A BAC clone containing the marsupial SLC16A2 was mapped to the end of the long arm of the tammar X chromosome and used in RNA FISH experiments to determine whether one
or both loci are transcribed in female cells. In male and female cells, only a single signal was found, indicating that the
marsupial SLC16A2 gene is silenced on the inactivated X. 相似文献
6.
7.
Random X inactivation in the mule and horse placenta 总被引:1,自引:0,他引:1
In eutherian mammals, dosage compensation of X-linked genes is achieved by X chromosome inactivation. X inactivation is random in embryonic and adult tissues, but imprinted X inactivation (paternal X silencing) has been identified in the extra-embryonic membranes of the mouse, rat, and cow. Few other species have been studied for this trait, and the data from studies of the human placenta have been discordant or inconclusive. Here, we quantify X inactivation using RNA sequencing of placental tissue from reciprocal hybrids of horse and donkey (mule and hinny). In placental tissue from the equid hybrids and the horse parent, the allelic expression pattern was consistent with random X inactivation, and imprinted X inactivation can clearly be excluded. We characterized horse and donkey XIST gene and demonstrated that XIST allelic expression in female hybrid placental and fetal tissues is negatively correlated with the other X-linked genes chromosome-wide, which is consistent with the XIST-mediated mechanism of X inactivation discovered previously in mice. As the most structurally and morphologically diverse organ in mammals, the placenta also appears to show diverse mechanisms for dosage compensation that may result in differences in conceptus development across species. 相似文献
8.
Differential expression pattern of XqPAR-linked genes SYBL1 and IL9R correlates with the structure and evolution of the region 总被引:3,自引:1,他引:3
D'Esposito M; Matarazzo MR; Ciccodicola A; Strazzullo M; Mazzarella R; Quaderi NA; Fujiwara H; Ko MS; Rowe LB; Ricco A; Archidiacono N; Rocchi M; Schlessinger D; D'Urso M 《Human molecular genetics》1997,6(11):1917-1923
9.
Margaret L. Delbridge Guy Longepied Danielle Depetris Marie-Genevieve Mattei Christine M. Disteche Jennifer A. Marshall Graves Michael J. Mitchell 《Chromosome research》2004,12(4):345-356
TSPY, a candidate gene for a factor that promotes gonadoblastoma formation (GBY), is a testis-specific multicopy gene family in the male-specific region of the human Y (MSY) chromosome. Although it was originally proposed that male-specific genes on the Y originated from a transposed copy of an autosomal gene (Lahn & Page 1999b), at least two male-specific genes (RBMY and SRY) descended from a formerly recombining X-Y identical gene pair. Here we show that a TSPY homologue with similar gene structure lies in conserved positions, close to SMCX, on the X chromosome in human (TSPX ) and mouse (Tspx). TSPX is widely expressed and subject to X inactivation. TSPX and TSPY therefore evolved from an identical gene pair on the original mammalian sex chromosomes. This supports the hypothesis that even male-specific genes on the Y chromosome may have their origin in ubiquitously expressed genes on the X. It also strengthens the case for TSPY as a candidate for GBY, since independent functional studies link TSPX to cell cycle regulation. 相似文献
10.
Alexander I. Shevchenko Irina S. Zakharova Eugeny A. Elisaphenko Nicolay N. Kolesnikov Siobhan Whitehead Christine Bird Mark Ross Jennifer R. Weidman Randy L. Jirtle Tatiana V. Karamysheva Nicolay B. Rubtsov John L. VandeBerg Nina A. Mazurok Tatyana B. Nesterova Neil Brockdorff Suren M. Zakian 《Chromosome research》2007,15(2):127-136
11.
Sex differences in sex chromosome gene expression in mouse brain 总被引:9,自引:0,他引:9
12.
Grati FR Sirchia SM Gentilin B Rossella F Ramoscelli L Antonazzo P Cavallari U Bulfamante G Cetin I Simoni G Miozzo M 《European journal of human genetics : EJHG》2004,12(4):272-278
Equivalent levels of X-linked gene products between males and females are reached by means of X chromosome inactivation (XCI). In the human and murine embryonic tissues, both the paternally and maternally derived X chromosomes (X(P) and X(M)) may be inactivated. In murine extra-embryonic tissues, X(P) is imprinted and always silenced; humans, unlike mice, can inactivate the X(M) in extra-embryonic lineages without an adverse outcome. This difference is probably due to the presence of imprinted placental genes on the murine X chromosome, but not on the human homologue, essential for placental development and function. An example is the paternally imprinted Esx1 gene; mice with a null maternally derived Esx1 allele show intrauterine growth restriction (IUGR) because of placental insufficiency. We investigated the imprinting status of the human orthologous Esx1 gene (ESX1L) in placental samples of four normal full-term and 13 IUGR female fetuses, in which we determined the XCI pattern. Our findings demonstrated that IUGR as well as normal placentas display XCI heterogeneity, thus indicating that the IUGR phenotype is not correlated with a preferential pattern of XCI in placentas. Moreover, ESX1L is equally expressed in IUGR and normal placentas, and shows the same methylation pattern in the presence of both random and skewed XCI. These findings provide evidence that ESX1L is not imprinted in human third-trimester placentas and there is no parent-of-origin effect of chromosome X associated with placental insufficiency. 相似文献
13.
14.
A 94 kb genomic sequence 3' to the murine Xist gene reveals an AT rich region containing a new testis specific gene Tsx 总被引:1,自引:1,他引:1
Simmler MC; Cunningham DB; Clerc P; Vermat T; Caudron B; Cruaud C; Pawlak A; Szpirer C; Weissenbach J; Claverie JM; Avner P 《Human molecular genetics》1996,5(11):1713-1726
15.
X chromosome inactivation is associated with a highly asynchronous pattern of DNA replication at most X-linked loci in females.
We studied the human HPRT locus, which is subject to X inactivation and expressed from only the active homolog, with the goal
of comparing replication properties between the active and inactive homologs in this region using a fluorescence in situ hybridization
approach. We found that in normal female lymphoblasts this locus is replicated in a highly asynchronous manner across a broad,
discrete 500–600 kb zone with earliest replication appearing at the gene coding sequence. This general timing profile is maintained
in normal male lymphoblasts, as well as in hamster x human hybrid cells containing the active human X chromosome. However,
the inactive human X chromosome in the hamster cell background does not appear to function in a fully equivalent manner to
the normal inactive X chromosome in female cells. Furthermore, reactivation of the inactive human X chromosome in a hamster
x human hybrid system by 5-azacytidine treatment and HAT selection restores early replication at the HPRT gene itself, but
does not change the overall domain behavior. 相似文献
16.
17.
Cloning and expression of the murine homologue of a putative human X-linked nuclear protein gene closely linked to PGK1 in Xq13.3 总被引:7,自引:1,他引:7
Gecz J.; Pollaord H.; Consalez G.; Villard L.; Stayton C.; Millasseau P.; Khrestchatisky M.; Fontes M. 《Human molecular genetics》1994,3(1):39-44
Several human inherited diseases have been localized to theXq13.3 region of the human X chromosome (X-linked dystonia withParkinsonism, sideroblasmic anemia, SCID, Menkes disease andX-linked mental retardation loci). Genes involved in the phenotypeshave been isolated for only two of them (Menkes and SCIDX).It was therefore interesting to isolate and characterize newgenes from the region. In a previous work (12 and Consalez etal,in preparation) we isolated a gene (XNP), located 350 Kb proximalto PGK1, potentially coding for a nuclear protein. We describehere the cloning and characterization of the murine homologue.The pattern of expression of the gene in the newborn mouse (especiallythe expression in particular reglons of the brain: optical lobe,frontal cortex, hippocampus and cerebellum), as well as theexpression in human tissues, suggests that this gene might beinvolved in neuronal differentiation. Among the different morbidphenotypes assigned to the region, X-linked mental retardationwould be the best candidate to be associated with this gene. 相似文献
18.
The mouse Sb1.8 gene located at the distal end of the X chromosome is subject to X inactivation 总被引:2,自引:1,他引:1
Sultana Razla; Adler David A.; Edelhoff Susanne; Carrel Laura; Lee Kwang ho; Chapman Verne C.; Willard Huntington F.; Disteche Christine M. 《Human molecular genetics》1995,4(2):257-263
The mouse homolog of the human DXS423E (SB1.8) gene has beenisolated by screening a mouse cDNA library. Like its human counterpart,the mouse Sb1.8 gene is X-linked, as shown by Southern blotanalysis and by in situ hybridization to metaphase chromosomes.Sb1.8 was sublocalized to band F of the mouse X chromosome,distal to Alas2 and proximal to DXPas1, which confirms a regionof conservation between band Xp11.21p11.22 in human andband XF in mouse. In situ hybridization also showed that theSmcx (Xe169) gene maps near Sb1.8 in band F. The Sb1.8 genewas shown to be highly conserved in mammals; partial DNA sequenceanalysis indicates 92% identity between the mouse and humangenes. In contrast to the human DXS423E gene, the mouse Sb1.8gene is subject to X Inactivation, as shown by restriction enzymeand sequence analysis of mRNA from mice with Searle's translocation(T(X; 16)16H). Absence of Sb1.8 expression from the inactivemouse X chromosome in vitro was confirmed by analysis of a cellline (Hobmski) in which the M.spretus X chromosome is inactivated.The Sb1.8 gene is a new member of a group of genes that escapeX inactivation in human, but are inactivated in mouse. 相似文献
19.
Nguyen DK Yang F Kaul R Alkan C Antonellis A Friery KF Zhu B de Jong PJ Disteche CM 《Genome research》2011,21(3):402-409
In Mus spretus, the chloride channel 4 gene Clcn4-2 is X-linked and dosage compensated by X up-regulation and X inactivation, while in the closely related mouse species Mus musculus, Clcn4-2 has been translocated to chromosome 7. We sequenced Clcn4-2 in M. spretus and identified the breakpoints of the evolutionary translocation in the Mus lineage. Genetic and epigenetic differences were observed between the 5'ends of the autosomal and X-linked loci. Remarkably, Clcn4-2 introns have been truncated on chromosome 7 in M. musculus as compared with the X-linked loci from seven other eutherian mammals. Intron sequences specifically preserved in the X-linked loci were significantly enriched in AT-rich oligomers. Genome-wide analyses showed an overall enrichment in AT motifs unique to the eutherian X (except for genes that escape X inactivation), suggesting a role for these motifs in regulation of the X chromosome. 相似文献
20.
Bicocchi MP Migeon BR Pasino M Lanza T Bottini F Boeri E Molinari AC Corsolini F Morerio C Acquila M 《European journal of human genetics : EJHG》2005,13(5):635-640
A basic tenet of the Lyon hypothesis is that X inactivation occurs randomly with respect to parental origin of the X chromosome. Yet, nonrandom patterns of X inactivation are common - often ascertained in women who manifest recessive X-linked disorders despite being heterozygous for the mutation. Usually, the cause of skewing is cell selection disfavouring one of the cell lineages created by random X inactivation. We have identified a three generation kindred, with three females who have haemophilia A because of extreme skewing of X inactivation. Although they have both normal and mutant factor VIII (FVIII) alleles, only the mutant one is transcribed; and, they share an XIST allele that is never transcribed. The skewing in this case seems to result from an abnormality in the initial choice process, which prevents the chromosome bearing the mutant FVIII allele from being an inactive X. 相似文献