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At least 289 records · Page 16Linked to original sources

PubMed1993

Cloning and sequencing of a cDNA fragment from Plasmodium chabaudi chabaudi that contains repetitive sequences coding for a potentially lysine-rich aspartic acid-rich protein.

Screening of a cDNA library (prepared in lambda gt11) of the blood stages of Plasmodium chabaudi chabaudi (AS) with immune serum has revealed an antigen the elicits a strong antibody response in infected mice. The clone (clone 6) expressing that antigen contains a 0.7 kb insert and produces a beta-galactosidase fusion protein of about 150 kDa. In Western blot analysis performed on parasite extracts, monoclonal antibodies and polyclonal sera prepared against the fusion protein revealed that the fusion protein contains part of a malarial protein of 93 kDa. Northern hybridization with clone 6 insert as probe detected a plasmodial RNA of about 3.2 kb, which could well code for a protein of this size. The insert hybridized to a single EcoRI fragment and a single HindIII fragment in genomic Southern blotting, suggesting that the gene is present in one copy in the P. chabaudi genome. The DNA sequence of clone 6 insert predicts a hydrophilic, acidic polypeptide consisting of seven repeats of 23-34 amino acids rich in lysine (24%) and aspartic acid (17.5%).

Amino Acid Sequence↗

PubMed1994

Cloning of thyroid hormone receptor genes expressed in metamorphosing flounder.

Two distinct cDNAs encoding thyroid hormone receptors (THRs) were cloned from a lambda gt10 library prepared from the whole bodies of metamorphosing flounder larvae (Paralichthys olivaceus). Deduced amino acid sequences of the two isolated cDNAs shared 96% and 92% homologies in their DNA- and hormone-binding domains, respectively. These were highly conserved when compared to THRs for other vertebrates: 88-96% in the DNA-binding domain and 84-94% in the hormone-binding domain. Other receptors in the nuclear receptor family showed lower homologies than those of THRs. Both THRs for the flounder had higher homologies with the alpha-type THRs of other vertebrates than with the beta-type. Thus, the two THRs for flounder were designated as fTHR alpha A and fTHR alpha B.

Amino Acid Sequence↗

PubMed1993

Isolation and characterization of a cDNA clone for a harvest-induced asparagine synthetase from Asparagus officinalis L.

A full-length cDNA clone (pTIP27) encoding asparagine synthetase (AS; EC 6.3.5.4) was isolated from a cDNA library prepared from the tip section (apex to 30 mm) of Asparagus officinalis L. spears. The cDNA clone encodes an mRNA of 1978 bp, giving a derived protein of 66.5 kD molecular mass. The derived amino acid sequence is 81% homologous to AS from Pisum sativum. Only low levels of transcript for AS could be detected in growing spears, roots, or ferns. However, AS mRNA levels began to increase in the tips of harvested spears after 2 h at 20 degrees C, and in the other sections of the spear after 4 h, suggesting that all sections of the spear were responding to the same postharvest signal. The results are discussed in relation to metabolic changes occurring in harvested spears.

Amino Acid Sequence↗

PubMed1998

Nucleotide and amino acid sequences of the monkey P450 2B gene subfamily.

The nucleotide sequence of a cDNA coding for monkey cytochrome P450 (P450) 2B has been determined. Using antibody against P450 CMLa which had been purified from hepatic microsomes of untreated cynomolgus monkeys, a cDNA clone with 2,275 bp insert (Mac2B) was isolated from a gamma gt11 cDNA library prepared from hepatic mRNA from an untreated rhesus monkey. The cloned insert was sequenced and found to contain an open reading frame coding for a polypeptide of 491 amino acids. The molecular weight calculated from the deduced amino acid sequence was 55,969. The N-terminal 34 amino acids encoded by Mac2B were identical to those determined by Edman degradation analysis of purified cynomolgus monkey P450 CMLa. The nucleotide and the deduced amino acid sequences of Mac2B which is now called CYP2B17 were the most similar to those of human P450 2B6 among the P450 2B subfamily and those sequences of Mac2B were 94% and 90% identical to those of human P450 2B6, respectively.

Amino Acid Sequence↗

PubMed1989

Sequence of human eosinophil-derived neurotoxin cDNA: identity of deduced amino acid sequence with human nonsecretory ribonucleases.

Several clones of human eosinophil-derived neurotoxin (EDN) cDNA have been isolated from a lambda gt10 cDNA library prepared from mRNA derived from noninduced HL-60 cells. The amino acid (aa) sequence deduced from the coding sequence of the EDN cDNA is identical to the aa sequence of urinary nonsecretory RNase. Comparison of the aa and/or nucleotide (nt) sequences of EDN and other proteins possessing ribonucleolytic activity, namely bovine seminal RNase, human and rat pancreatic RNases, eosinophil cationic protein (ECP), and human angiogenin, shows extensive identity at half-cystine residues and at aa of active sites. Differences in aa sequences at the active sites are often the result of single nt changes in the codons. The data presented here support the concept of a RNase gene superfamily containing secretory and nonsecretory RNases, angiogenin, EDN and ECP.

Amino Acid Sequence↗

PubMed1990

Sequence of a cDNA that specifies the uridine diphosphate N-acetyl-D-glucosamine:dolichol phosphate N-acetylglucosamine-1-phosphate transferase from Chinese hamster ovary cells.

We have isolated a portion of the uridine diphosphate N-acetyl-D-glucosamine:dolichol phosphate N-acetyl-glucosamine-1-phosphate transferase gene (GTR2) from the genome of a tunicamycin-resistant clonal Chinese hamster ovary cell line, 3E11. The genomic fragment was selected by its hybridization to the yeast ALG-7 gene at low stringency. A 2.46-kilobase cDNA was isolated from a library prepared from 3E11 mRNA and probed with GTR2. The cDNA contained an open reading frame that encodes a protein of 408 amino acids with a molecular mass of 44.9 kDa. This protein was 43% identical in amino acid sequence to the protein of 448 amino acids encoded by the ALG-7 gene. The GTR2 gene fragment contained sequences for four exons coding for the carboxyl-terminal half of the protein. Transferase DNA sequences in 3E11 cells were 12-fold elevated over wild-type cells and 25-fold elevated when 3E11 cells were grown in the presence of tunicamycin. Transferase RNA levels in 3E11 cells were also elevated over wild-type levels but appeared unchanged by the presence of tunicamycin in the medium.

Amino Acid Sequence↗

PubMed1990

The human N-formylpeptide receptor. Characterization of two cDNA isolates and evidence for a new subfamily of G-protein-coupled receptors.

Two variants of the human N-formylpeptide chemoattractant receptor have been isolated from a CDM8 expression library prepared from mRNA of human myeloid HL-60 cells differentiated to the granulocyte phenotype with Bt2cAMP. Both recombinant receptors, fMLP-R26 and fMLP-R98, are 350 amino acids long (Mr 38,420); they differ from each other by two residue changes at positions 101 and 346 and by significant differences in the 5' and 3' untranslated regions. Both clones were able to transfer to COS-7 cells the capacity to specifically bind a new and highly efficient hydrophilic derivative of N-formyl-Met-Leu-Phe-Lys, referred to as fMLPK-Pep12. Photolabeling experiments revealed that the glycosylated form of the fMLP receptor in COS cells has a molecular weight (Mr 50,000-70,000) similar to that observed for the native receptor in differentiated HL-60 cells. Northern blot analysis revealed a major transcript of 1.6-1.7 kb and two minor hybridization signals of 2.3 and 3.1 kb, suggesting a related family of receptors. The complex hybridization pattern obtained with restricted genomic DNA was consistent with either two genes encoding fMLP receptor isoforms or a single gene with at least one intron in the coding sequence. Sequence comparison established that the fMLP receptor belongs to the G-protein-coupled receptor superfamily. The structural similarities observed with RDC1, a receptor isolated from a dog thyroid cDNA library, which shares weak homologies with other members of the family, suggests that the fMLP receptor is representative of a new subfamily.

Amino Acid Sequence↗

PubMed2002

Molecular cloning of trypsin cDNAs and trypsin gene expression in the salmon louse Lepeophtheirus salmonis (Copepoda: Caligidae).

The salmon louse, Lepeophtheirus salmonis, is a marine ectoparasitic copepod that infects salmonid fishes. We are studying the interactions between this parasite and its salmonid hosts, as it is a common cause of disease in both wild and farmed stocks of salmon. In this paper, we report on the cloning and sequencing of seven trypsin-like enzymes from a cDNA library prepared from whole body preadult female and male L. salmonis. The predicted trypsin activation peptides are 23 or 24 residues in length, considerably longer than previously reported activation peptides of other animals. Differences in the putative signal and activation peptide sequences of the trypsin isoforms suggest that these forms differ in their regulation and function. The calculated molecular weights of the trypsins range from 23.6 to 23.7 kDa. There are eight cysteine residues, which suggest the presence of four disulfide bridges. These trypsins are very similar (>or=46% aa identity) to other crustacean trypsins and insect hypodermins. Using in situ hybridization techniques trypsinogen expression could be identified in all three cell types of the midgut.

Amino Acid Sequence↗

PubMed2005

[Ribosomal protein genes highly expressed in swamp eel gonads].

8 cDNA clones have been isolated from a cDNA library prepared from swamp eel testies by macroarray. DNA sequence analysis and database search showed that they encode 8 proteins which are highly homologous to 40S ribosomal proteins S4,S9,S16,S17,S20 and 60S riobosomal proteins L7, L18a,L29. Phylogenetic trees (ML) based on ribosomal protein genes from swamp eel and other organisms has been reconstructed, which showed that ribosomal protein genes were highly conserved during evolution. These results suggested that ribosomal protein genes as house keeping genes may play roles in developmental regulation such as sexual differentiation and can also be used as markers for the study of molecular evolution.

Amino Acid Sequence↗

PubMed1984

A gene sequence expressed only in undifferentiated EC, EK cells and testes.

A clone, EC1, has been isolated from a cDNA library prepared from 4-day embryoid bodies formed by suspension culture of PSMB EC cells. This clone has been used to screen a variety of RNA sources including adult tissues, embryonal carcinoma (EC), and endoderm cell lines. A 3-kb poly(A)+ RNA species was found to be present only in undifferentiated EC cells and adult mouse testes. This species was significantly reduced in testes of W/Wv mice compared with wild-type at this locus. Germ cells and their progeny are therefore implicated as the source of the RNA in testes. Hybrid-selected RNA from PSMB could be translated in vitro into a 35-kd protein, but no translatable message was evident in either PYS-2 (parietal), or PSA5-E (visceral) endoderm cell lines. DNA sequencing of the EC1 insert revealed that it is 744 bp in length, the 3' 460 bp of which are in open reading frame. Comparison with known sequences have shown no significant homology. EC1 subclones in M13 have been used to generate single-stranded probes for hybridisation to RNA in situ in tissue sections. Hybridisation of the strand complementary to RNA produces a signal limited to the central regions of embryoid bodies formed on suspension culture of embryo-derived EK cells coinciding with the presence of undifferentiated cells. Probing of a mouse genomic library and Southern blots of liver DNA with EC1 reveals that the gene is present as a single copy.

Amino Acid Sequence↗

PubMed1995

Nucleotide and primary sequences of a rice endosperm cDNA are extensively homologous to elongation factor 1 beta'.

A rice endosperm cDNA expression library prepared with poly (A+) RNA was screened with polyclonal antibodies raised against purified 16 kD globulin. One of the three positive antigen producing clones was completely sequenced. This clone was composed of 759 bp and contained a single open reading frame encoding 192 amino acids. The 3' untranslated region did not include a typical polyadenylation signal, AATAAA. The cDNA encodes a protein of molecular weight 21,064 with an isoelectric point of 4.3. The amino acid sequence of the rice seed cDNA shows extensive homology to elongation factor 1 beta' from several sources, including human and Artemia salina. The molecular weight of rice seed EF-1 beta' is smaller than the others, and it lacks a conserved phosphorylation site that has been implicated in regulating nucleotide exchange activity.

Amino Acid Sequence↗

PubMed1992

Isolation and sequencing of a cDNA clone encoding the 85 kDa human lysosomal sialoglycoprotein (hLGP85) in human metastatic pancreas islet tumor cells.

A full length cDNA for a human lysosomal membrane sialoglycoprotein (hLGP85) was isolated as a probe of the cDNA of rat LGP85 (rLGP85) from the cDNA library prepared from total mRNA of QGP-1NL cells, a human pancreatic islet tumor cell with a high metastatic activity. The deduced amino acid sequence shows that hLGP85 consists of 478 amino acid residues (MW. 54,289). The protein has 10 putative N-glycosylation sites and 2 hydrophobic regions at the NH2- and near the COOH-termini, respectively. Thus, both domains probably constitute putative transmembrane domains. It exhibits 86% and 79% sequence similarities in amino acids and nucleic acids to rat lysosomal membrane sialoglycoprotein (rLGP85), respectively. The protein contained the short cytoplasmic tail at the COOH-terminus which does not form the glycine-tyrosine sequence (GY motif), the so-called lysosomal targetting signal.

Adenoma, Islet Cell↗

PubMedDate not supplied

Molecular cloning and spatial expression of an ApL1 cDNA for the large subunit of ADP-glucose pyrophosphorylase from Arabidopsis thaliana.

A cDNA, ApL1a, corresponding to a homologue of the large subunit of ADP-glucose pyrophosphorylase (AGPase), has been isolated/characterised by screening a cDNA library prepared from leaves of Arabidopsis thaliana, followed by rapid amplification of cDNA 3'-ends (3'-RACE). Within the 1685 nucleotide-long sequence (excluding polyA tail), an open reading frame encodes a protein of 522 amino acids (aa), with a calculated molecular weight of 57.7 kDa. The derived aa sequence does not contain any discernible transit peptide cleavage site motif, similarly to two other recently sequenced full-length Arabidopsis homologues for AGPase, and shows ca. 58-78% identity to homologous proteins from other plants/tissues. The corresponding gene was found to be expressed in all tissues examined (rosette and stem leaves, stems, flowers and fruits). The ubiquitous expression of the gene is consistent with its critical role in starch synthesis in Arabidopsis.

Amino Acid Sequence↗

PubMed1998

Isolation of a set of ripening-related genes from strawberry: their identification and possible relationship to fruit quality traits.

The ripening of strawberry (Fragaria ananassa Duch.), a non-climacteric fruit, is a complex developmental process that involves many changes in gene expression. To understand how these changes relate to the biochemistry and composition of the fruit the specific genes involved have been examined. A high-quality cDNA library prepared from ripe strawberry fruit was differentially screened for ripening-related clones using cDNA from ripe and white fruits. From 112 up-regulated clones obtained in the primary screen, 66 differentially expressed clones were isolated from the secondary screen. The partial sequences of these cDNAs were compared with database sequences and 26 families of non-redundant clones were identified. Northern analysis confirmed that all of these cDNAs were ripening-enhanced. The expression of many of their corresponding genes was negatively regulated in auxin-treated fruit. These sequences, several of which are novel to fruits, encode proteins involved in key metabolic events including anthocyanin biosynthesis, cell wall degradation, sucrose and lipid metabolism, protein synthesis and degradation, and respiration. These findings are discussed in relation to the role of these genes in determining fruit quality characteristics.

Base Sequence↗

PubMed2005

Identification of a new class of recombinant prolamin genes in wheat.

A novel storage protein gene with obvious [corrected] chimeric structure was isolated from an immature kernel-specific cDNA library prepared from the old Hungarian wheat [corrected] variety, Bánkúti 1201. This clone contains gamma-gliadin sequences in the 5' region and LMW-glutenin sequences on the 3' end. A frameshift mutation was also introduced by the putative recombination event. Hence, the amino acid sequence of the C-terminal region was transformed to a completely new polypeptide. Based on this finding, 7 additional recombinant prolamin genes of similar structure were isolated with specific PCR primers. The 8 chimeric clones seem to be derived from 4 individual gamma-gliadin and 3 LMW-glutenin sequences. These genes show remarkable diversity in size, gliadin:glutenin ratio, frameshift mutations, and sulphur content. The putative functional characteristics of the chimeric polypeptides and problems related to the origin of the encoding genes are discussed.

Amino Acid Sequence↗

PubMed2000

Molecular cloning and characterization of a cDNA encoding proline transporter in rice.

A cDNA encoding a proline (Pro) transporter (ProT) was isolated and characterized from a cDNA library prepared from 14-d-old seedlings of Oryza sativa cv. Akibare. The deduced amino acid sequence of the rice ProT protein (OsProT) had 68.8% homology to the ProT protein 1 from Arabidopsis thaliana and 59.6% homology to that from Lycopersicon esculentum. Northern blot analysis revealed that the gene for OsProT (OsProT) was expressed in all organs examined, comparatively strongly in leaf sheath and stem. Salt treatment did not induce expression of OsProT but strongly induced expression of the gene for delta1-pyrroline-5-carboxylate synthetase (P5CS), a key enzyme in Pro biosynthesis. Southern blot analysis revealed that OsProT has a gene family. OsProT specifically transported L-Pro in a transport assay using Xenopus laevis oocytes.

Amino Acid Sequence↗

PubMed1997

Molecular cloning of gilthead seabream (Sparus aurata) pituitary transcription factor GHF-1/Pit-1.

We report here the complete nucleotide sequence of a cDNA clone encoding Sparus aurata GHF-1/Pit-1 isolated from an expression library prepared from gilthead seabream pituitary gland poly(A)+ RNA. The cDNA sequence (saGHF-1/Pit-1) encodes a protein of 371 amino acids (aa) containing a POU domain (aa 194-343) and a transactivation, STA domain (aa 1-128). Northern blot hybridization of pituitary RNA detected a single 3.0 kb band and a rat GHF-1/Pit-1 antiserum was found to immunoreact with pituitary protein species of 42 kDa by Western blot analysis. When compared with mammalian GHF-1/Pit-1 aa sequence, the POU and STA domains of saGHF-1/Pit-1 protein show 83% and 48% aa identity, respectively. In spite of the low homology of the transactivation domain, saGHF-1/Pit-1 is able to activate the transcription of the human growth hormone promoter.

Amino Acid Sequence↗

PubMed2003

cDNA cloning and characterization of a novel SNX gene differentially expressed in previtellogenic oocytes of gibel carp.

To understand the molecular events governing fish oogenesis, a multiple technique was used to identify the genes differentially expressed at different phases during fish oogenesis. This technique is a combination of suppression subtractive hybridization, SMART cDNA synthesis and RACE-PCR. Here we report the cDNA cloning and expression characterization of a novel SNX gene based on its differential transcription between previtellogenic and fully mature oocytes in naturally gynogenetic gibel carp. First, a cDNA fragment selectively expressed in previtellogenic oocytes was identified and used to screen a SMART cDNA library prepared from the same mRNA sample by RACE-PCR for cloning fully length cDNA. The full length cDNA was 1392-bp long and coded for a novel SNX protein with 225 amino acids. The 5' UTR had 72 bp and 3' UTR had 642 bp. Unlike most of maternal genes that are transcribed after vitellogenesis and stored in oocytes, this gene is expressed at a higher level in the previtellogenic oocytes and at a much lower level in fully matured oocytes. However, RT-PCR analysis of tissues showed it was ubiquitous transcription. The novel gene is named fish sorting nexin (fSNX), because it contains a conserved PX domain. The fact which major expression of the gene occurs in the previtellogenic oocytes suggests that it might have an important function in the oogenesis.

Amino Acid Sequence↗