A Instituição através de uma caderneta de cromos

Existem variadas formas de comunicação para dar a conhecer uma instituição, que seja ela privada ou pública. Considerando por um lado a sua missão e por outro lado o seu pequeno orçamento, o Centro Ciência Viva do Algarve (CCVAlg) optou por desenvolver um projeto que permitisse criar um produto educativo e lúdico e ao mesmo tempo transmitir a imagem de uma instituição promotora da transferência de conhecimento científico. Nesse sentido e de forma a apresentar um produto multidisciplinar que aproveitasse as especificidades da região, foi decidido desenvolver um projeto sobre a Ria Formosa, que além de oferecer um ambiente natural de grande riqueza também permite abordar temas como a economia, a história, a arquitetura ou ainda a geologia, entre outros. De seguida, foi necessário encontrar não só os parceiros que possuam os conhecimentos científicos que se pretendia transmitir mas igualmente o parceiro que desenvolvesse o suporte que alberga-se o projeto. Os parceiros científicos foram naturalmente surgindo, tratando-se de entidades que são reconhecidas pelo seu trabalho no sistema lagunar de ilhas barreiras da Ria Formosa, como é o caso do Parque Natural da Ria Formosa (PNRF-ICNF), da Universidade do Algarve (UALG) e da Associação RIAS. Quanto ao parceiro técnico, o CCVAlg teve a sorte de ser contactado pela empresa COLARA que desenvolve cadernetas digitais de cromes, produtos que respondem perfeitamente ao objetivo de associar uma vertente lúdica à vertente educativa. Assim nasceu a caderneta digital de cromes sobre a Ria Formosa que integra i) o conhecimento científico; ii) a divulgação científica; iii) a educação não formal e interativa e iv) a comunicação institucional. O lançamento da caderneta terá lugar na 1a semana da Ria Formosa organizada pelo Instituto de Conservação da Natureza e da Floresta que decorrerá de 4 a 8 de Abril nos 5 concelhos que abrigam a Ria Formosa.Acknowledgement to Colara companyinfo:eu-repo/semantics/publishedVersio

Identification and characterization of two distinct PPP1R2 isoforms in human spermatozoa

Background: Protein Ser/Thr Phosphatase PPP1CC2 is an alternatively spliced isoform of PPP1C that is highly enriched in testis and selectively expressed in sperm. Addition of the phosphatase inhibitor toxins okadaic acid or calyculin A to caput and caudal sperm triggers and stimulates motility, respectively. Thus, the endogenous mechanisms of phosphatase inhibition are fundamental for controlling sperm function and should be characterized. Preliminary results have shown a protein phosphatase inhibitor activity resembling PPP1R2 in bovine and primate spermatozoa. Results: Here we show conclusively, for the first time, that PPP1R2 is present in sperm. In addition, we have also identified a novel protein, PPP1R2P3. The latter was previously thought to be an intron-less pseudogene. We show that the protein corresponding to the pseudogene is expressed. It has PPP1 inhibitory potency similar to PPP1R2. The potential phosphosites in PPP1R2 are substituted by non-phosphorylable residues, T73P and S87R, in PPP1R2P3. We also confirm that PPP1R2/PPP1R2P3 are phosphorylated at Ser121 and Ser122, and report a novel phosphorylation site, Ser127. Subfractionation of sperm structures show that PPP1CC2, PPP1R2/PPP1R2P3 are located in the head and tail structures. Conclusions: The conclusive identification and localization of sperm PPP1R2 and PPP1R2P3 lays the basis for future studies on their roles in acrosome reaction, sperm motility and hyperactivation. An intriguing possibility is that a switch in PPP1CC2 inhibitory subunits could be the trigger for sperm motility in the epididymis and/or sperm hyperactivation in the female reproductive tract.publishe

Influence of cysteine residues on monoamine oxidases catalysis

Monoamine oxidases (MAO), types A and B, are flavin-containing enzymes important in the regulation of biogenic amines, including the neurotransmitters, serotonin and dopamine. Cysteine modification inactivates MAO and alters the flavin redox properties, yet the crystal structure has shown that there are no conserved cysteines in the active site of MAO B and that the cysteine 365, modified after inactivation by a cyclopropylamine, was on the surface. The aim of this project was to find how the cysteine residues influence MAO catalysis. MAO A and B cysteine mutants to alanine were constructed and expressed in P. pastoris. MAO A C374A was purified and characterised kinetically. The mutant was active but had decreased Kcₐₜ/kₘ values with a series of substrates compared to the native enzyme. The Kᵢ values for inhibitors were not changed. Mechanism-based inactivators, cyclopropylamines, showed the same pattern as the substrates. Spectra studies and free thiol counts established that 1-phenylcyclopropylamine (1-PCPA) forms a flavin adduct whereas 2-phenylcyclopropylamine (2-PCPA) and A-cyclo- α-methylbenzylamine (N-CαMBA) form adducts with a cysteine in both native and mutant MAO A. Thus, the cysteine modified by N-CαMBA in MAO A is not the 374, as it would be expected by correspondence to the MAO B cysteine 365. For the 1-PCPA and N-CαMBA, the partition ratio was decreased by more than 50%. The data suggest the mutation of cysteine 374 decreases the efficiency of MAO A catalytic process without affecting the ligand binding. A revised mechanism for inactivation of MAO by cyclopropylamines is proposed

Identification and characterization of two distinct PPP1R2 isoforms in human spermatozoa

Background: protein Ser/Thr Phosphatase PPP1CC2 is an alternatively spliced isoform of PPP1C that is highly enriched in testis and selectively expressed in sperm. Addition of the phosphatase inhibitor toxins okadaic acid or calyculin A to caput and caudal sperm triggers and stimulates motility, respectively. Thus, the endogenous mechanisms of phosphatase inhibition are fundamental for controlling sperm function and should be characterized. Preliminary results have shown a protein phosphatase inhibitor activity resembling PPP1R2 in bovine and primate spermatozoa. Results: here we show conclusively, for the first time, that PPP1R2 is present in sperm. In addition, we have also identified a novel protein, PPP1R2P3. The latter was previously thought to be an intron-less pseudogene. We show that the protein corresponding to the pseudogene is expressed. It has PPP1 inhibitory potency similar to PPP1R2. The potential phosphosites in PPP1R2 are substituted by non-phosphorylable residues, T73P and S87R, in PPP1R2P3. We also confirm that PPP1R2/PPP1R2P3 are phosphorylated at Ser121 and Ser122, and report a novel phosphorylation site, Ser127. Subfractionation of sperm structures show that PPP1CC2, PPP1R2/PPP1R2P3 are located in the head and tail structures. Conclusions: the conclusive identification and localization of sperm PPP1R2 and PPP1R2P3 lays the basis for future studies on their roles in acrosome reaction, sperm motility and hyperactivation. An intriguing possibility is that a switch in PPP1CC2 inhibitory subunits could be the trigger for sperm motility in the epididymis and/or sperm hyperactivation in the female reproductive tract