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91.
Roberto de la Herrán Miguel Hermida Juan Andres Rubiolo Jèssica Gómez-Garrido Fernando Cruz Francisca Robles Rafael Navajas-Pérez Andres Blanco Paula Rodriguez Villamayor Dorinda Torres Pablo Sánchez-Quinteiro Daniel Ramirez Maria Esther Rodríguez Alberto Arias-Pérez Ismael Cross Neil Duncan Teresa Martínez-Peña Ana Riaza Adrian Millán M. Cristina De Rosa Davide Pirolli Marta Gut Carmen Bouza Diego Robledo Laureana Rebordinos Tyler Alioto Carmelo Ruíz-Rejón Paulino Martínez 《Molecular ecology resources》2023,23(4):886-904
Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 single nucleotide polymorphism variants in the follicle stimulating hormone receptor (fshr) consistent with an XX/XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. The fshr gene displayed differential expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 nonsynonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis. 相似文献
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96.
Identification and cellular localization of the actin-binding protein ABP-120 from Entamoeba histolytica 总被引:1,自引:0,他引:1
Several actin-binding proteins participate in the morphological changes that occur during amoeboid movement. The gene encoding one of these proteins, the gelation factor ABP-120, was identified and characterized from trophozoites of Entamoeba histolytica . The sequence contains 2574 nucleotides, with an open reading frame of 858 amino acids, giving a protein of 93 kDa belonging to the spectrin family. The N-terminal domain of ABP-120 from E. histolytica revealed a consensus site for actin binding homologous to the actin-binding sites of ABP-120 of Dictyostelium discoideum , α-actinin and spectrin. Analysis of the central domain revealed the presence of four repeats of a 73-amino-acid motif constituting 31% of the protein. In addition, a stretch of 105 amino acids was highly divergent when compared with the C-terminal domain of D. discoideum ABP-120. This sequence showed short motifs that are homologous to microtubule-binding domains. We found that ABP-120 from E. histolytica binds to F-actin. In addition, upon motility of the parasite, this protein localized in the pseudopod and the uroid region, implying a role for ABP-120 in movement and capping of surface receptors in E. histolytica . 相似文献
97.
Miguel Arroyo José María Sánchez-Montero José Vicente Sinisterra 《Biotechnology Techniques》1996,10(4):263-266
Summary We describe a qualitative method to predict the pre-equilibration aw, system value in which, covalent immobilized lipase B from Candida antarctica to sepharose and silica, displayed best synthetic activity. The methodology is based in the analysis of the water adsorption isotherms of the biocatalyst in air and in the organic solvent. The biocatalyst is active at pre-equilibration aw values higher than the divergence point between both isotherms. In addition, native and immobilized lipase display highest activity if the biocatalyst is pre-equilibrated at aw=P point. For preparative purposes, the validity of the method was proved in the esterification of racemic 2-(4-isobutyl phenyl) propionic acid with 1-propanol in isooctane at long reaction time. 相似文献
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Antonio del Castillo-Olivares Alicia Esteban del Valle Javier Márquez Ignacio NÚñez de Castro Miguel ángel Medina 《Journal of bioenergetics and biomembranes》1995,27(6):605-611
Ehrlich cell plasma membrane ferricyanide reductase activity increased in the presence of mastoparan, a generic activator of G proteins, using either whole cells or isolated plasma membrane fractions. Agents that increase intracellularcAMP also increased the rate of ferricyanide reduction by Ehrlich cells. For the first time, evidence is shown on a modulation of plasma membrane redox system bycGMP. In fact, permeant analogs ofcGMP, dibutyrylcGMP, and 8-bromo-cGMP increased the rate of ferricyanide reduction by the Ehrlich cell plasma membrane redox system. Furthermore, specific inhibition ofcGMP-phosphodiesterases by dipyridamole was also accompanied by an enhancement in the rate of ferricyanide reduction. On the other hand, treatments expected to increase cytoplasmic Ca2+ concentrations were accompanied by a remarkable stimulation of the reductase activity. Taking all these data together, it seems that the Ehrlich cell plasma membrane redox system is under a multiple and complex regulation by different signal transduction pathways involving G proteins, cyclic nucleotides, and Ca2+ ions. 相似文献
100.
Jesús Zurdo Miguel A. Centeno José A. Odriozola Concepción Fernández-Cabrera Juan M. Ramírez 《Photosynthesis research》1995,46(1-2):363-369
In previous work (Zurdo J, Fernández-Cabrera C and Ramírez JM (1993) Biochem J 290: 531–537), it had been shown that selective extraction of the carotenoid from the light-harvesting protein 2 (LH2) of Rhodobacter capsulatus induced the dissociation of 800-nm absorbing bacteriochlorophyll (Bchl), a 10-nm red shift of 854-nm Bchl, and a decrease of the stability of the protein in detergent solution. In the present study, the Fourier transform Raman and near-infrared circular dichroism spectra of native and carotenoid-depleted LH2 membrane preparations were compared. It was found that while the coupled carbonyls of 854-nm Bchl remained specifically H-bonded to the peptides after carotenoid extraction, the optical activity of the near-infrared electronic transition was significantly altered. Given the excitonic origin of such optical activity, our data suggest that carotenoid extraction elicits a rearrengement of the chromophore cluster and of the associated polypeptide subunits. This implies a significant role of the carotenoid in maintaining the native quaternary structure of the protein, which would be consistent with the observed dissociation of 800-nm Bchl and the loss of solubilized LH2 stability that result from carotenoid removal. There is no evidence for a similar role of the carotenoid in the LH1 protein.Abbreviations Bchl
bacteriochlorophyll
- FT
Fourier transform
- CD
circular dichroism
- LH1 and LH2
the bacterial light-harvesting proteins 1 and 2
In memoriam of Daniel I. Arnon. 相似文献