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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have analyzed the junction regions of inserted elements within the human amylase gene complex. This complex contains five genes which are expressed at high levels either in the pancreas or in the parotid gland. The proximal 5'-flanking regions of these genes contain two inserted elements. A gamma-actin pseudogene is located at a position 200 base pairs upstream of the first coding exon. All of the amylase genes contain this insert. The subsequent insertion of an endogenous retrovirus interrupted the gamma-actin pseudogene within its 3'-untranslated region. Nucleotide sequence analysis of the inserted elements associated with each of the five human amylase genes has revealed a series of molecular events during the recent history of this gene family. The data indicate that the entire gene family was generated during primate evolution from one ancestral gene copy and that the retroviral insertion activated a cryptic promoter.
Mol Cell Biol 1990 Jun
PMID:Retroviral and pseudogene insertion sites reveal the lineage of human salivary and pancreatic amylase genes from a single gene during primate evolution. 169 56

We reported previously that the herpes simplex virus type 1 (HSV-1) thymidine kinase reporter gene (tk) was expressed in the testes of transgenic mice when coupled to the promoter of a liver-specific mouse major urinary protein (MUP) gene. Here we show that HSV-1 tk is also expressed in the testis when coupled to a MUP pseudogene promoter, to a truncated MUP promoter that is not active in the liver, and to the promoter of the bovine thyroglobulin gene. Furthermore, HSV-1 tk itself was expressed in the testis, although its normal expression had been disabled by removing an upstream regulator of transcription. In every case, the same multiple transcripts were observed, with their 5' ends located downstream of the normal HSV-1 tk translation initiation codon. We conclude that the transcription of HSV-1 tk in the testis is directed by a cryptic TATA box-independent promoter located in the coding region of the gene. The longest HSV-1 thymidine kinase (TK) polypeptides synthesized in the testis were shorter than full-length TK and probably result from translational initiation at Met46 and Met60, the second and third ATG codons of the tk reading frame. Male mice of most transgenic lines were sterile, and the severity of the lesion in spermatogenesis was directly related to the level of TK expression. In the most highly expressing lines, sperm counts were low and morphologically defective sperm were common. In other sterile lines, TK was expressed at a lower level and sperm counts were normal but sperm motility was greatly reduced. Lines with the lowest levels of HSV-1 TK expression were fertile. HSV-1 TK was expressed in germ line cells, mainly in the haploid spermatids. However, low-level HSV-1 TK activity was found in the testis before the first germ cells entered meiosis, showing that if expression is confined to the germ cells, it also occurs in spermatogonia.
Mol Cell Biol 1991 Aug
PMID:The herpes simplex virus type 1 thymidine kinase is expressed in the testes of transgenic mice under the control of a cryptic promoter. 171 6

Molecular cloning experiments indicate the presence of two distinct CRF genes in the sucker genome encoding independent 162-amino-acid precursors, which both consist of a signal sequence, succeeded by a cryptic peptide and subsequently by the hormone moiety. The two 41-amino-acid CRF peptides differ by an Ala-->Val substitution at amino acid position 28. CRF transcripts are primarily found in the sucker pre-optic nucleus (PON), to a much lesser extent in the lateral tuberal nucleus (LTN). In contrast, urotensin I (U I) encoding mRNA is equally present in both tissues. In urophysectomized fish, U I mRNA is elevated especially in LTN tissue, while CRF mRNA levels remain more or less constant in the PON and LTN regions.
Mol Mar Biol Biotechnol 1991 Sep
PMID:Corticotropin-releasing factor (CRF) gene family in the brain of the teleost fish Catostomus commersoni (white sucker): molecular analysis predicts distinct precursors for two CRFs and one urotensin I peptide. 172 76

This study evaluates five cryptic plasmid-derived DNA probes in a 4-h slot-blot hybridization assay for the detection of Chlamydia trachomatis in cultures and clinical specimens. The probes, consisting of either the entire cloned 7.5 kbp cryptic plasmid pSE8 or one of four Hin dIII/Eco RI fragments measuring 710, 1055, 710, and 500 bp, respectively, were labelled with Photoprobe biotin. The probe was detected using a streptavidin-alkaline phosphatase conjugate followed by addition of BCIP and NBT. The sensitivity of the assay, using 25 ng of probe DNA, ranged from 50 pg (with the entire plasmid as probe) to 5 ng (with the 500 bp fragment as probe). A total of 103 reference strains of Chlamydia trachomatis and other bacteria were tested for reactivity with the probes. All 18 reference strains of C. trachomatis hybridized with the probes. None of the DNA from the heterologous organisms tested was found to hybridize with any of the probes. A total of 174 samples taken from patients visiting the STD clinic at the University Hospital, University of Seville were used in the study. The overall sensitivity of the assay, using the 710 bp biotinylated probe was 94.5% compared to culture while the specificity was 97.5%. Positive and negative predictive values were 96.5% and 97.5%, respectively. It appears that the plasmid-derived probes used in this study could serve as useful tools for the rapid and specific detection of Chlamydia trachomatis in cell cultures and clinical specimens.
Mol Cell Probes 1991 Dec
PMID:Evaluation of a DNA probe of plasmid origin for the detection of Chlamydia trachomatis in cultures and clinical specimens. 177 80

A 1.5 kb cryptic plasmid was isolated from Helicobacter pylori. Low-stringency hybridization analysis using this plasmid as a DNA probe revealed base sequence homology with other plasmids in this species. Nucleotide sequence analysis identified an open reading frame encoding a putative polypeptide of 25 kDa. This protein showed marked amino acid sequence similarity to replication-initiation proteins commonly found in small plasmids endogenous to Gram-positive bacteria which replicate by the 'rolling-circle' mechanism. Sequence motifs corresponding to the origins-of-replication consensus sequences were found on this cryptic plasmid. DNA and oligonucleotide probes to these plasmid replication sequences were used in hybridization analysis to identify similar sequences in other H. pylori plasmids. We believe this is the first plasmid isolated from a Gram-negative bacterium to show replication determinants characteristic of the 'rolling-circle' group of plasmids from Gram-positive bacteria. The cloned plasmid will be used to develop a shuttle-vector for H. pylori.
Mol Microbiol 1991 Oct
PMID:Characterization of a plasmid from Helicobacter pylori encoding a replication protein common to plasmids in gram-positive bacteria. 179 53

We have constructed an expression vector carrying the Escherichia coli his operon control region to study the ability of defined segments of DNA to cause rho factor-mediated transcription termination both in vivo and in vitro. We have previously identified a consensus motif consisting of a region of high cytosine over guanosine content common to several cryptic intracistronic transcription termination elements unmasked by polar mutations. We show that a DNA fragment possessing features similar to the ones previously identified is capable of causing rho-mediated mediated release of transcripts in vivo and in vitro. The efficiency of termination depends on the length and efficiency of termination depends on the length and relative cytosine over guanosine ratio of the element.
Mol Microbiol 1991 Dec
PMID:A cytosine- over guanosine-rich sequence in RNA activates rho-dependent transcription termination. 180 43

A two-site model for the binding of U1 small nuclear ribonucleoprotein particle (U1 snRNP) was tested in order to understand how exon partners are selected in complex pre-mRNAs containing alternative exons. In this model, it is proposed that two U1 snRNPs define a functional unit of splicing by base pairing to the 3' boundary of the downstream exon as well as the 5' boundary of the intron to be spliced. Three-exon substrates contained the alternatively spliced exon 4 (E4) region of the preprotachykinin gene. Combined 5' splice site mutations at neighboring exons demonstrate that weakened binding of U1 snRNP at the downstream site and improved U1 snRNP binding at the upstream site result in the failure to rescue splicing of the intron between the mutations. These results indicate the stringency of the requirement for binding a second U1 snRNP to the downstream 5' splice site for these substrates as opposed to an alternative model in which a certain threshold level of U1 snRNP can be provided at either site. Further support for the two-site model is provided by single-site mutations in the 5' splice site of the third exon, E5, that weaken base complementarity to U1 RNA. These mutations block E5 branchpoint formation and, surprisingly, generate novel branchpoints that are specified chiefly by their proximity to a cryptic 5' splice site located at the 3' terminus of the pre-mRNA. The experiments shown here demonstrate a true stimulation of 3' splice site activity by the downstream binding of U1 snRNP and suggest a possible mechanism by which combinatorial patterns of exon selection are achieved for alternatively spliced pre-mRNAs.
Mol Cell Biol 1991 Dec
PMID:Combinatorial splicing of exon pairs by two-site binding of U1 small nuclear ribonucleoprotein particle. 183 32

A 14-kDa antigen present on the surface of uterine microfilariae of Onchocerca spp. has been identified using monoclonal antibodies. The antigen was also found in skin microfilariae, but in a masked or cryptic form. A complementary DNA clone encoding the epitope recognised by one of the monoclonal antibodies was identified in a lambda gt11 library. Nucleotide sequencing revealed that the 233-bp cDNA fragment codes for the carboxy-terminus of the antigen. The deduced amino acid sequence consists of three hydrophobic domains with high potential for beta-sheet formation. The amino-terminal hydrophobic domain is followed by 4 positively charged residues (positions 22-25) which contribute to the rather basic character of the protein. Another interesting feature of the polypeptide is its richness in phenylalanine (12.7%). From the sequence information, a synthetic peptide was synthesised which was recognised by one of the monoclonal antibodies directed against the 14-kDa antigen and a small number of sera from patients with onchocerciasis. The relevance of this to vaccination is discussed.
Mol Biochem Parasitol 1991 May
PMID:Studies on a 14-kilodalton surface protein of Onchocerca microfilariae. 185 66

The first intron of the early region 3 from adenovirus type 2 contains a cryptic 5' splice site, Dcr1, 74 nucleotides downstream from the natural site D1. The cryptic site can be activated when the natural site is inactivated by mutagenesis. To investigate the basis for selection between a natural and a cryptic 5' splice site, we searched for cis-acting elements responsible for the exclusive selection of the natural site. We show that both the relative intrinsic strength of the sites and the sequence context affect the selection. A 120-nucleotide segment located at the 3' end of exon 1 enhances splicing at the proximal site D1; in its absence the two sites are used according to their strength. Thus, three cis-acting elements are involved in the silencing of the cryptic site: the sequence of D1, the sequence of Dcr1, and an upstream exonic sequence. We show that the exonic element folds, in solution, into a 113-nucleotide-long stem-loop structure. We propose that this potential stem-loop structure which is located 6 nucleotides upstream of the exon 1-intron junction is responsible for the preferential use of the natural 5' splice site.
Mol Cell Biol 1991 Sep
PMID:Identification of a specific exon sequence that is a major determinant in the selection between a natural and a cryptic 5' splice site. 187 41

This study evaluates a cryptic plasmid-derived DNA probe in a dot-blot hybridization assay of 4-h duration, using both known bacterial isolates and clinical specimens. The probe, consisting of a 237 bp segment of the plasmid-encoded gene cppB, sequences of which are also found in the chromosome, was labelled with digoxigenin-11-dUTP. The sensitivity of the probe was approximately 25 pg of DNA or 500 cfu of Neisseria gonorrhoeae. A total of 170 reference strains of Neisseria gonorrhoeae and other related bacteria were tested for reactivity with the probe. All N. gonorrhoeae strains, including three plasmid-free strains, hybridized with the probe. Among the heterologous bacterial cultures, only one strain of N. cinerea reacted with the probe when the cell concentration was 5 x 10(6) cfu. The probe was also evaluated in a clinical study. A total of 201 patients visiting the STD clinic at the University Hospital, University of Seville, participated in the study. The sensitivity of the assay was 95% while the specificity was 98%. Positive and negative predictive values were 97% and 98%, respectively. It appears that the plasmid-derived probe used in this study could serve as a useful tool in the rapid and specific detection of Neisseria gonorrhoeae in clinical specimens.
Mol Cell Probes 1991 Feb
PMID:Evaluation of a DNA probe of plasmid origin for the detection of Neisseria gonorrhoeae in cultures and clinical specimens. 190 56


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