Search results for "Complementary DNA"

Functional characterization of the plastidial 3-phosphoglycerate dehydrogenase family in Arabidopsis.

2013

This work contributes to unraveling the role of the phosphorylated pathway of serine (Ser) biosynthesis in Arabidopsis (Arabidopsis thaliana) by functionally characterizing genes coding for the first enzyme of this pathway, 3-phosphoglycerate dehydrogenase (PGDH). We identified two Arabidopsis plastid-localized PGDH genes (3-PGDH and EMBRYO SAC DEVELOPMENT ARREST9 [EDA9]) with a high percentage of amino acid identity with a previously identified PGDH. All three genes displayed a different expression pattern indicating that they are not functionally redundant. pgdh and 3-pgdh mutants presented no drastic visual phenotypes, but eda9 displayed delayed embryo development, leading to aborted emb…

ISOLATION OF RAT CDNA CLONES CODING FOR THE AUTOANTIGEN SS-B/LA - DETECTION OF SPECIES-SPECIFIC VARIATIONS

1993

Clones of cDNA coding for the autoantigen La (or SS-B) were isolated from a library made from rat liver. A comparison of the rat La cDNA (encoding from nt 38 to 1281 for rat La protein) with the sequences known for human and bovine La protein resulted in the identification of species-specific inserts. The inserts seem to be the result of multiplication of flanking sequences during evolution. In addition to these variations, we observed that rat La cDNAs exhibit non-canonical polyadenylation sites. Finally, a databank search resulted in the identification of a DNA sequence originally termed as TAG or TSG20X (GenBank accession No. X61893) which represents the C terminus of mouse La/SS-B prote…

Noncanonical RNAs from transcripts of the Drosophila muscleblind gene.

2006

It has become increasingly evident that eukaryotic cells produce RNA molecules from coding genes with constitutions other than those of typically spliced mRNA transcripts. Here we describe new cDNAs from the Drosophila melanogaster muscleblind (mbl ) locus that identify two such atypical RNA molecules: RNAs containing an incomplete exon 2 tandem repetition (mblE2E2#) or having exons with a different order compared to the corresponding genomic DNA (mblE2E3#E2#; exon scrambling). The existence of exon duplications and rearrangements in the genomic locus that might explain such cDNAs was ruled out by genomic Southern blotting and in silico analysis of the Drosophila genome sequence. The incomp…

Sequence evolution, processing, and posttranslational modification of zonadhesin D domains in primates, as inferred from cDNA data

2005

Zonadhesin is a mammalian transmembrane sperm ligand. Precursor zonadhesin essentially consists of MAM (meprin/A5 antigen/mu receptor tyrosine phosphatase) domains, a mucin-like repeat, and D domains (homologous to von Willebrand D). Recent immunovisualization and binding assays indicate that zonadhesin D domains 1–3 bind postacrosomally to the zona pellucida. This feature has attracted considerable interest in the evolution of zonadhesin and its possible biological and biomedical implications. Previous molecular evolutionary analyses, however, were confined to cDNA sequences of only few distantly related species. Moreover, except for rabbit and pig, little is known about zonadhesin’s proce…

Axolotl MHC architecture and polymorphism.

1999

The MHC of the urodele amphibian Ambystoma mexicanum consists of multiple polymorphic class I loci linked, so far as yet known, to a single class II B locus. This architecture is very different from that of the anuran amphibian Xenopus. The number of class I loci in the axolotl can vary from 6 to 21 according to the haplotypes as shown by cDNA analysis and Southern blot studies in families. These loci can be classified into seven sequence groups with features ranging from the class Ia to the class Ib type. All individuals express genes from at least three of the seven groups, and all individuals possess the class Ia-like type.

A tunicate (Botryllus schlosseri) cDNA reveals similarity to vertebrate antigen receptors

1996

RNA-binding ability of PIPP in requires the entire protein

2003

Post-transcriptional fate of eukaryotic mRNAs depends on association with different classes of RNA-binding proteins (RBPs). Among these proteins, the cold-shock domain (CSD)-containing proteins, also called Y-box proteins, play a key role in controlling the recruitment of mRNA to the translational machinery, in response to environmental cues, both in development and in differentiated cells. We recently cloned a rat cDNA encoding a new CSD-protein that we called PIPPin. This protein also contains two putative double-stranded RNA-binding motifs (PIP(1) and PIP(2)) flanking the central CSD, and is able to bind mRNAs encoding H1 degrees and H3.3 histone variants. In order to clarify the role of…

Molecular cloning and evolution of lobster hemocyanin.

2001

In the American lobster, Homarus americanus, oxygen is transported by a hemocyanin that is composed 2 x 6 subunits. N-terminal sequencing show the presence of three distinct subunit types (alpha, beta and gamma). We cloned the cDNA of one of these subunits that belong to the alpha-type. It encodes a hemocyanin subunit of 654 amino acids with a molecular mass of 84.8 kDa, which is synthesized in the hepatopancreas. Phylogenetic analyses of the crustacean hemocyanin sequences show two well-separated clades, which correspond to the alpha and gamma-type subunits. Sequences of beta-type subunits are still unknown. The gamma-sequences have evolved about 15% faster than the alpha-subunits, consist…

Response of rainbow trout transcriptome to model chemical contaminants.

2004

We used high-density cDNA microarray in studies of responses of rainbow trout fry at sublethal ranges of beta-naphthoflavone, cadmium, carbon tetrachloride, and pyrene. The differentially expressed genes were grouped by the functional categories of Gene Ontology. Significantly different response to the studied compounds was shown by a number of classes, such as cell cycle, apoptosis, signal transduction, oxidative stress, subcellular and extracellular structures, protein biosynthesis, and modification. Cluster analysis separated responses to the contaminants at low and medium doses, whereas at high levels the adaptive reactions were masked with general unspecific response to toxicity. We fo…

A statistical analysis of the three-fold evolution of genomic compression through frame overlaps in prokaryotes

2007

Abstract Background Among microbial genomes, genetic information is frequently compressed, exploiting redundancies in the genetic code in order to store information in overlapping genes. We investigate the length, phase and orientation properties of overlap in 58 prokaryotic species evaluating neutral and selective mechanisms of evolution. Results Using a variety of statistical null models we find patterns of compressive coding that can not be explained purely in terms of the selective processes favoring genome minimization or translational coupling. The distribution of overlap lengths follows a fat-tailed distribution, in which a significant proportion of overlaps are in excess of 100 base…