共查询到20条相似文献,搜索用时 31 毫秒
1.
V. Morawala-Patell J. M. Gualberto L. Lamattina J.-M. Grienenberger G. Bonnard 《Molecular & general genetics : MGG》1998,258(5):503-511
In wheat mitochondria, the gene coding for subunit 2 of the NADH-ubiquinone oxidoreductase (nad2) is divided into five exons located in two distant genomic regions. The first two exons of the gene, a and b, lie 22 kb downstream
of exons c, d, and e, on the same DNA strand. All introns of nad2 are group II introns. A trans-splicing event is required to join exons b and c. It involves base pairing of the two precursor
RNAs in the stem of domain IV of the intron. A gene coding for tRNATyr is located upstream of exon c. In addition to splicing processes, mRNA editing is also required for the correct expression
of nad2. The mature mRNA is edited at 36 positions, distributed over its five exons, resulting in 28 codon modifications. Editing
increases protein hydrophobicity and conservation.
Received: 11 August 1997 / Accepted: 2 February 1998 相似文献
2.
We have determined the nucleotide sequence of the human fibroblast growth factor receptor 3 (FGFR3) gene, including 800 bp
of the 5′-flanking region and compared the sequence with the previously published murine Fgfr3 gene. The organization of the gene is highly conserved between man and mouse. We used the intron sequences to design a set
of primers that allow amplification of the 17 exons (2–18) that encode the complete open reading frame. Using these primers
the FGFR3 gene can be amplified at the genomic level, which significantly facilitates mutational screening.
Received: 27 December 1996 / Accepted: 6 March 1997 相似文献
3.
4.
Oh-Sung Jeon Chan-Shick Kim Sam-Pin Lee Sung Ku Kang Chang-Myung Kim Bong-Gyoon Kang Yoonkang Hur In-Jung Kim 《Journal of Plant Biology》2006,49(5):403-408
A cDNA and genomic clone (CuLEA5) encoding a group 5 late embryogenesis abundant protein (Lea5) was isolated from citrus fruit cDNA and genomic libraries.
Sequence analysis indicated that the clone contains an open reading frame of 97 amino acids, and that the genomic structure
is composed of two exons and one intron. A comparison of its amino sequence with other plant proteins showed that Lea5 proteins
can be classified into two types - gymnosperm and angiosperm — based on a P-segment sequence designated by this study. Examination
of its expression patterns indicated thatCuLEA5 has important roles during the development or ripening of seedless fruits and leaves inCitrus. The 5′-flanking region of the genomic DNA contains a number of putative hormonal- and stress-responsive elements. This is
the first report that describes the expression ofLea5 during fruit ripening, as well as the sequence characteristics of its promoter region. 相似文献
5.
Saskia H. M. van Erp Brian Dixon Felipe Figueroa Egbert Egberts René J. M. Stet 《Immunogenetics》1996,44(1):49-61
In this study we report the finding of three representatives of a new group of major histocompatibility complex class I sequences
in carp: Cyca-12 (Cyca-UA1
*
01), a full-length cDNA; Cyca-SP1 (Cyca-UAW1), a polymerase chain reaction (PCR) fragment from cDNA; and Cyca-G11 (Cyca-UA1
*
02), a partial genomic clone. Comparison of the amino acid sequences of Cyca-12, Cyca-SP1, and Cyca-G11 with classical and non-classical class I sequences from other species shows considerable conservation in regions that
have been shown to be involved in maintaining the structure and function of class I molecules. The genomic organization of
Cyca-12 has been elucidated by analysis of a partial genomic clone Cyca-G11, in combination with PCR amplifications on genomic DNA of a homozygous individual. Although the genomic organization
is similar to that found in class I genes from other species, the 3′ untranslated region contains an intron which is unprecedented
in class I genes, and intron 2 is exceptionally large (±14 kilobases). Southern blot analysis indicates the presence of multiple
related sequences. In phylogenetic analyses, the Cyca-UA sequences cluster with class I genes from zebrafish and Atlantic salmon, indicating that the ancestral gene arose before
the salmonid/cyprinid split, approximately 120 – 150 million years ago. The previously reported class I Cyca-Z genes from carp and Caau-Z genes from goldfish cluster as a completely separate lineage. A polyclonal antiserum (anti-Cyca12) was raised against a recombinant fusion protein containing most of the extracellular domains of Cyca-12. The antibodies showed substantial reactivity to the recombinant protein and an M
r
45 000 protein in membrane lysates of spleen and muscle, as well as to determinants present on leucocytes in fluorescence-activated
cell sorter analyses. Erythrocytes and thrombocytes were found to be negative.
Received: 6 November 1995 / Revised: 16 January 1996 相似文献
6.
Expression of the seed plant mitochondrial nad5 gene involves two trans-splicing events that remove fragmented group II introns and join the small, central exon c to exons b and d. We show that in both monocot and eudicot plants, extensive mis-splicing of the bi-partite intron 2 takes place, resulting in the formation of aberrantly spliced products in which exon c is joined to various sites within exon b. These mis-spliced products accumulate to levels comparable to or greater than that of the correctly spliced mRNA. We suggest that mis-splicing may result from folding constraints imposed on intron 2 by base-pairing between exon a and a portion of the bi-partite intron 3 downstream of exon c. Consistent with this hypothesis, we find that mis-splicing does not occur in Oenothera mitochondria, where intron 3 is further fragmented such that the predicted base-pairing region is not covalently linked to exon c. Our findings suggest that intron fragmentation may lead to mis-splicing, which may be corrected by further intron fragmentation. 相似文献
7.
Identification of transposon-like elements in non-coding regions of tomato ACC oxidase genes 总被引:4,自引:0,他引:4
B. Blume C. S. Barry A. J. Hamilton M. Bouzayen D. Grierson 《Molecular & general genetics : MGG》1997,254(3):297-303
1-aminocyclopropane-1-carboxylate (ACC) oxidase, which catalyses the terminal step in ethylene biosynthesis, is encoded by
a small multigene family in tomato that is differentially expressed in response to developmental and environmental cues. In
this study we report the isolation and sequencing of approximately 2 kb of 5′-flanking sequence of three tomato ACC oxidase
genes (LEACO1, LEACO2, LEACO3) and the occurrence of class I and class II mobile element-like insertions in promoter and intron regions of two of them.
The LEACO1 upstream region contains a 420-bp direct repeat which is present in multiple copies in the tomato genome and is very similar
to sequences in the promoters of the tomato E4 and 2A11 genes. The region covering the repeats resembles the remnant of a retrotransposon. Two copies of a small transposable element,
belonging to the Stowaway inverted repeat element family, have been found in the 5′-flanking sequence and the third intron of LEACO3.
Received: 8 August 1996 / Accepted: 4 November 1996 相似文献
8.
9.
K. Kofler S. K?chl W. Parson M. Erdel G. Utermann G. Baier 《Molecular & general genetics : MGG》1998,259(4):398-403
Members of the protein kinase C (PKC) family of serine/threonine kinases, in particular PKCθ, play critical roles in the regulation
of differentiation and proliferation of T lymphocytes. In this study the genomic structure of the human PRKCQ gene that encodes
PKCθ was determined. Two genomic P1 clones were isolated from human P1 libraries using the PKCθ cDNA as a probe and have been
used to confirm the assignment of the single PRKCQ locus to chromosome 10p15 by FISH analysis. The PRKCQ locus, the first
mammalian PKC gene locus characterized so far, spans approximately 62 kb and is composed of 15 coding exons and 14 introns,
varying in size between 98 and 16 000 bp. All exon-intron boundaries have been determined by long-range PCR and subsequent
DNA sequence analysis. Comparison with other known genomic PKC genes reveals a high degree of homology to the genomic organization
of the Drosophila melanogaster dPRKC gene. Alignment of the intron positions in the PRKCQ gene with the intron locations in the dPRKC gene indicates that
the sites of seven of the 14 PRKCQ introns are exactly conserved. Exons 5 (32 bp), 11 (174 bp) and 12 (92 bp) share highest
similarity in size, organization and primary structure with their counterparts in the Drosophila gene. On the basis of this
knowledge of the genomic PRKCQ locus, a directed search for potential genetic polymorphisms and/or genetic abnormalities involved
in human genetic disease(s) can now be initiated.
Received: 6 February 1998 / Accepted: 25 May 1998 相似文献
10.
The decay-accelerating factor (DAF, CD55) protects cells from autologous complement attack on self cell membranes. We have
previously reported that the seventh exon encoding the serine/threonine-rich(S/T)-abc region of the guinea pig DAF gene is composed of five homologous repeats of about 51 base pairs, and that differential usage of these repeats produces
the various lengths observed in the S/T region of guinea pig DAF. In this study, we found that the seventh intron of the guinea pig DAF gene was wholly composed of 18 tandem repeats homologous to the repeating unit of the S/T-abc exon. This type of repetitive
structure, although the number of repeats was variable, was also found in the corresponding exons and introns of all DAF genes of other species so far tested including human and seven other primates and mouse, in which alternative splicing in
this region has not been found. This suggested that generation of the repetitive sequences spanning the exon and intron regions
had occurred before the diversification of these species. In addition, all the intron sequences of the tested DAF genes had no stop codon when they were presumably translated in the same reading frame as the seventh and eighth exons, except
for that of one of two duplicated mouse DAF genes. These findings and significant interspecies identities of the intron sequence suggest that the intron sequence conceivably
could be translated in some tissues and/or in some stages of development although to date we have not yet succeeded in detecting
mRNA for this region.
Received: 7 July 1997 / Revised: 11 August 1997 相似文献
11.
K. Schmidt-Bleek V. Heiser O. Thieck A. Brennicke L. Grohmann 《Molecular & general genetics : MGG》1997,253(4):448-454
The intrinsic 28.5-kDa iron-sulfur protein of complex I in the mitochondrial respiratory chain is encoded in the nucleus
in animals and fungi, but specified by a mitochondrial gene in trypanosomes. In plants, the homologous protein is now found
to be encoded by a single-copy nuclear gene in Arabidopsis thaliana and by two nuclear genes in potato. The cysteine motifs involved in binding two iron-sulfur clusters are conserved in the
plant protein sequences. The locations of the seven introns, with sizes between 60 and 1700 nucleotides, are identical in
the A. thaliana and the two potato genes, while their primary sequences diverge considerably. The A+T contents of the intron sequences range
between 61% and 73%, as is characteristic for dicot plants, but are in some instances not higher than in the adjacent exons.
Here, differences in T content may instead serve to discriminate exons and introns. In potato, both genes are expressed, with
the highest levels found in flowers. Sequence similarities between the homologous nuclear and mitochondrial genes indicate
that the nuclear forms in animals and plants originate from the endosymbiont genome.
Received: 28 May 1996 / Accepted: 22 August 1996 相似文献
12.
13.
Southern analysis of Eco RI-digested BALB/c liver DNA reveals four T-cell receptor Tcra-V3-hybridizing DNA fragments, which are of sizes 18.0, 12.0, 8.0, and 2.1 kilobases, respectively. These four Tcra-V3-hybridizing genomic DNA were isolated from a BALB/c genomic library. Restriction and Southern analysis of the genomic DNA
clones showed that each of the Tcra-V3-hybridizing Eco RI DNA fragments harbors only a single Tcra-V3 gene. The DNA sequences of coding regions of the four Tcra-V3 family members were determined. These sequences show very limited divergence from one another. Comparisons of BALB/c Tcra-V3 sequences with published Tcra-V3 sequences expressed in different strains of mice reveal substantial allelic polymorphism. Sequence similarity searches retrieved
homologous rat, cattle, and human genes. The scarcity of coding sequence divergence among members of the Tcra-V3 family and the more substantial allelic polymorphism may be general features of the T-cell receptor V-alpha chain-encoding
gene families.
Received: 11 April 1996 / Revised: 26 May 1996 相似文献
14.
15.
Mitsuyoshi Ueda Shin-ichi Sanuki Hiroyuki Kawachi Kaori Shimizu Haruyuki Atomi Atsuo Tanaka 《Archives of microbiology》1997,168(1):8-15
Citrate synthase, an essential enzyme of the tricarboxylic acid cycle in mitochondria, was purified from acetate-grown Candida tropicalis. Results from SDS-PAGE and gel filtration showed that this enzyme was a dimer composed of 45-kDa subunits. A citrate synthase
cDNA fragment was amplified by the 5′-RACE method. Nucleotide sequence analysis of this cDNA fragment revealed that the deduced
amino acid sequence contained an extended leader sequence which is suggested to be a mitochondrial targeting signal, as judged
from helical wheel analysis. Using this cDNA probe, one genomic citrate synthase clone was isolated from a yeast λEMBL3 library.
The nucleotide sequence of the gene encoding C. tropicalis citrate synthase, CtCIT, revealed the presence of a 79-bp intron in the N-terminal region. Sequences essential as yeast splicing motifs were present
in this intron. When the CtCIT gene including its intron was introduced into Saccharomyces cerevisiae using the promoter UPR-ICL, citrate synthase activity was highly induced, which strongly indicated that this intron was correctly spliced in S. cerevisiae.
Received: 20 November 1996 / Accepted: 25 February 1997 相似文献
16.
The interleukin (IL)-1 family of proteins plays an important role in inflammatory and defense mechanisms. The recently characterized
IL1HY1 cDNA encodes a new member of the IL-1 receptor antagonist family (IL-1ra). In this report, we describe the complete nucleotide
sequence of the human IL1HY1 gene. We sequenced approximately 7600 nucleotides and found four coding exons ranging in size from 55 to 2288 nucleotides.
The 5′ untranslated region is formed by one of two alternatively used exons and one invariably present exon which also contains
the region encoding the first nine amino acids of the protein. IL1HY1 and IL-1ra intron positions are well conserved within the protein-coding region, providing evidence that these genes arose from a duplication
of a primordial IL-1 receptor antagonist gene.
Received: 15 October 1999 / Revised: 30 December 1999 相似文献
17.
Genetic variation in the porcine myogenin gene locus 总被引:37,自引:0,他引:37
Ann Soumillion Jo H. F. Erkens Johannes A. Lenstra Günther Rettenberger Marinus F. W. te Pas 《Mammalian genome》1997,8(8):564-568
The myogenin (MYOG) gene fulfills a key function in muscle differentiation by controlling the onset of myoblast fusion and the establishment
of myofibers. In meat-producing animals like pigs and cattle, myofiber numbers have been related to growth capacity. We have
characterized the porcine MYOG gene to detect genetic variation at this locus and to relate it to growth characteristics. MYOG gene fragments were isolated by PCR on genomic DNA and by screening a genomic library with a mixture of the four human MyoD
cDNA fragments. Both the exons and promoter region were very similar to the human and mouse genes. Southern blot analysis
of 105 unrelated pigs revealed three polymorphic MspI sites, located in the promoter region, the second intron, and at the 3′ side of the gene. PCR-RFLP tests detecting four
MYOG alleles were developed. PCR analysis of a panel of pig–rodent somatic cell hybrids confirmed the genetic localization of
MYOG on pig Chromosome (Chr) 9. The PCR-RFLP tests and microsatellite markers on Chr 9 offer the possibility to genotype large
numbers of pigs for studies of genetic linkage to meat deposition and growth characteristics.
Received 13 October 1996 / Accepted: 16 March 1992 相似文献
18.
Juan-José Fuentes Carles Pucharcós Melanie Pritchard X. Estivill 《Human genetics》1997,101(3):346-350
We have developed a simple, straightforward procedure to isolate exons from cloned human genomic DNA. The method is PCR based
and relies upon the conservation of splice-site sequences and the frequency of Alu repeat elements in the genome to capture coding sequences. We designed two different sets of primers: a primer from each
end of the Alu element and primers with the 5′ or 3′ splice-site consensus sequences. Putative exons were amplified by PCR using YAC DNA
as starting material. We applied Alu-splice PCR to two overlapping YACs, 72H9 and 860G11, from human chromosome 21. Sequence and northern analysis of 37 initial
clones resulted in the identification of five novel exons.
Received: 17 July 1997 / Accepted: 28 August 1997 相似文献
19.
20.
Dongli Zhao Le Li Qian Wang Guoyin Kai Xiang Wang Lu Wang Xiaofen Sun Kexuan Tang 《Biologia》2006,61(3):327-329
Based on the cDNA sequence encoding taxane 2α-O-benzoyltransferase (TBT) from Taxus yunnanensis (Gen-Bank Accession No.: AY970522), genomic sequences of TBTs from T. yunnanensis (TyTBT) and T. cuspidata (TcuTBT) were cloned for the first time. They both contain only one intron. The finding that the introns of TyTBT and TcuTBT are more diverse than their exons implies that the gene diversity is more within introns than within exons, which may be
important for keeping the functions of the genes. 相似文献