The XXVII Congress of the SEBBM (Lleida, September 2004), authors who have signed this collaboration between universities in the Basque Country and Victoria (Canada) presented his studies on the interaction of nucleoplasmin with chromatin early somatic after fertilization of the oocyte. Nucleoplasmin, first described as a molecular chaperone protein (for RA Lackey in 1978) is an acidic protein of the oocytes whose activity is regulated by phosphorylation.  Read the rest of this entry »

Most sporadic colorectal cancers are initiated by activating mutations in the route Want (wingless type), whose products are implicated Eph receptors (Ephraim’s) and its ligands.A study on the development of colorectal cancer sample, for the first time that the activity of Eph receptors (responsible for controlling the structure of intestinal epithelium through repulsive interactions with their legends) cancels the progression of benign to malignant tumors. Read the rest of this entry »

The action of neurotrophins, factors that modulate the differentiation, maturation and neuronal regeneration, and even death of neurons, is carried out through specific receptors. Among them, the Trk A tyrosine kinase with activity. After activation, these receptors give rise to an intracellular signaling cascade, which culminates with the expression of certain genes.

So far, these receptors were found only in vertebrates, and the search had been barren of invertebrates, made in the two most widely used models, Drosophila melanogaster and Caenorhabditis elegans, as their appearance was related to the evolution of early vertebrates. However, a paper published in Development, in collaboration between the universities of Barcelona and Lleida, has identified the Trk receptor gene in the genome of Branchiostoma floridae, an amphioxus genome equipped with a pre-archetypal gene duplication arose during the evolution of vertebrates. Read the rest of this entry »

Three papers were signed at a joint CSIC and the University of Salamanca describe the identification and characterization of a new family of serine-threonine kinases of human carcinoma, in the course of evolution, separated from the branch that subsequently caused the casein kinases. The catalytic domain of this new family VRK (vaccinia-related kinases) is related to the vaccinia virus B1R protein.  Read the rest of this entry »

Metalloproteinase’s, enzymes involved in the process of hydrolysis and digestion of proteins, play vital roles in physiological processes and diseases such as Alzheimer’s disease, arthritis, osteoporosis and cancer. We have seen one of these metalloproteinase’s, the hCPA4 (human carboxypeptidase’s A4), is over expressed in some tumor cell lines. A team of researchers from the CSIC and the Autonomous University of Barcelona have solved the atomic structure of this enzyme complex formed and Latex in, the only known endogenous inhibitor of Metallocarboxypeptidases. Read the rest of this entry »

Aware of the importance of electrostatic and hydrophobic interactions in the formation of complexes that allow an efficient electron transfer between
molecules, such as the ferredoxin NADP + reeducates (FNR) and ferredoxin (Fd). The FNR catalyzes the transfer of electrons sequentially from two molecules of Fd to NADP + molecule in order to store energy in the form of reducing power NADPH.

We have seen that certain residues in the FNR are also critical for interaction with flavodoxin (Fled), redo protein binding of flaying mononucleotide, though,
so far, has not found any clue to her that waste may be associated with side
chains of FNR.
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Identification of a new serine protease, signed at the
Graduate Institute of Oncology, University of Oviedo. The authors cloned a human
DNA encoding this new enzyme, named polisher’s 2 the second identified human
enzyme with several tandem serine protease domains in its amino acid sequence.
The article describes its complex organization in domains, also present in the
sequences of the two polisher’s rat and mouse, and similar to the polisher’s 1.
The first of three serine protease domain contains all the characteristics of
these enzymes, while the second and third lack a key residue, so that it
predicts them to be catalytically inactive.

 
The authors make a series of enzyme assays with peptide substrates commonly used
to assess serine proteases, and the results show that both the polisher’s 2
completes its first serine protease domain hydrolyzed these peptides, but with
the particularity that the activity of the isolated domain is greater than that
of the whole protein, indicating that the two catalytic domains inactive
polisher’s 2 can modulate the activity of the first domain. As for human tissues
which express this enzyme, the authors identified by its presence in Northern
blot fetal kidney, skeletal muscle, liver, placenta, prostate and heart, as well
as tumor cell lines derived from Aden carcinomas of the lung and colon. The
signatories conclude that this new polyprotein is a secreted enzyme whose three
protease domains remain as integral parts of a single polypeptide chain.

Nicotinic acetylcholine receptors are allotter membrane proteins that belong to a large family of ligand-gated ion channels that mediate transmission in the cholinergic system. Structurally, it consists of five subunits of one of the four types alpha, beta, gamma and delta, with the alpha subunit is composed of nine possible subtypes (alpha 1-9) and four beta (beta-1-4). The binding of agonists to these receptors generates a sequence of conformational changes resulting in channel opening. Previously, this team at the Institute of Neurosciences of a joint center of the Miguel Hernandez University and the CSIC had shown that a residue of the alpha-7 nicotinic receptor, the aspartame in position 266 of the connecting sequence between Tran membrane domains M2 and M3, intervenes in the relationship between agonist binding and channel opening.

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The DNA replication process can be a source of genetic instability. As shown in this study, researchers from the Department of Genetics at the University of Seville, a defective deposition of histones leads to recombinagenic structure formation during replication of DNA generated by such genomic instability. Read the rest of this entry »

A cyclin-dependent kinases Cdk4 and Cdk6 are attributed a crucial role in the initiation of cell cycle in response to mitogenic stimuli. They are, therefore, be targets toward which the biomedical sciences and pharmaceutical industry directed its efforts to intervene in the trigger mechanisms of cancer (some ant tumor drugs in Phase II clinical research, which has placed considerable trust, act inhibiting its activity). Read the rest of this entry »