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Y-chromosome microsatellite markers can be effectively isolated by combining representational difference analysis (RDA) with the screen of a bacterial artificial chromosome (BAC) library in a domestic horse (Equus caballus) showing a single halotype. It helps us to use this knowledge extended to other mammalian species besides humans, with regard to sex-specific differences in ecology and behavior.

White-rot (WR) fungi are pivotal decomposers of dead organic matter in forest ecosystems and typically use a large array of hydrolytic and oxidative enzymes to deconstruct lignocellulose. However, the extent of lignin and cellulose degradation may vary between species and wood type. Here, we combined comparative genomics, transcriptomics and secretome proteomics to identify conserved enzymatic signatures at the onset of wood-decaying activity within the Basidiomycota genus Pycnoporus. We observed a strong conservation in the genome structures and the repertoires of protein-coding genes across the four Pycnoporus species described to date, despite the species having distinct geographic distributions. We further analysed the early response of P. cinnabarinus, P. coccineus and P. sanguineus to diverse (ligno)-cellulosic substrates. We identified a conserved set of enzymes mobilized by the three species for breaking down cellulose, hemicellulose and pectin. The co-occurrence in the exo-proteomes of H2O2-producing enzymes with H2O2-consuming enzymes was a common feature of the three species, although each enzymatic partner displayed independent transcriptional regulation. Finally, cellobiose dehydrogenase-coding genes were systematically co-regulated with at least one AA9 lytic polysaccharide monooxygenase gene, indicative of enzymatic synergy in vivo. This study highlights a conserved core white-rot fungal enzymatic mechanism behind the wood-decaying process., (© The Author(s) 2020. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.)

The genus Pycnoporus forms a group of four species known especially for producing high redox potential laccases suitable for white biotechnology. A sample of 36 Pycnoporus strains originating from different geographical areas was studied to seek informative molecular markers for the typing of new strains in laboratory culture conditions and to analyse the phylogeographic relationships in this cosmopolitan group. ITS1-5.8S-ITS2 ribosomal DNA and partial regions of β-tubulin and laccase lac3-1 gene were sequenced. Phylogenetic trees inferred from these sequences clearly differentiated the group of Pycnoporus cinnabarinus strains from the group of Pycnoporus puniceus strains into strongly supported clades (100% bootstrap value). Molecular clustering based on lac 3-1 sequences enabled the distribution of Pycnoporus sanguineus and Pycnoporus coccineus through four distinct, well supported clades and sub-clades. A neotropical sub-clade, grouping the P. sanguineus strains from French Guiana and Venezuela, corresponded to P. sanguineus sensu stricto. A paleotropical sub-clade, clustering the strains from Madagascar, Vietnam and New Caledonia, was defined as Pycnoporus cf. sanguineus. The Australian clade corresponded to P. coccineus sensu stricto. The Eastern Asian region clade, clustering the strains from China and Japan, formed a P. coccineus-like group. Laccase gene (lac 3-1) analysis within the Pycnoporus species can highlight enzyme functional diversity associated with biogeographical origin., (© 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.)

Aims: Exploitation of natural biodiversity in species Pycnoporus coccineus and Pycnoporus sanguineus to screen for a new generation of laccases with properties suitable for the lignin-processing sector., Methods and Results: Thirty strains originating from subtropical and tropical environments, mainly isolated from fresh specimens collected in situ, were screened for laccase activity. On the basis of levels of enzyme activity and percentage of similarity between protein sequences, the laccases from strains BRFM 938, BRFM 66 and BRFM 902 were selected for purification and characterization. Each BRFM 938, BRFM 66 and BRFM 902 laccase gene encoded a predicted protein of 518 amino acids; the three deduced proteins showed 68.7-97.5% similarity with other Polyporale laccases. The three laccases (59.5-62.9 kDa with 7-10% carbohydrate content) had high redox potentials (0.72-0.75 V vs normal hydrogen electrode at pH 6), remained highly stable up to 75-78 degrees C and at pH 5-7 mixtures, and were resistant to methyl and ethyl alcohols, acetonitrile and dimethylsulfoxide at concentrations as high as 50% (v/v). The best laccase-1-hydroxybenzotriazole systems permitted almost 100% of various polyphenolic dye decolourization and oxidation of adlerol and veratryl alcohol., Conclusions: The three laccases showed complementary biochemical features. BRFM 938 laccase had the highest thermo- and pH stability, catalytic efficiency towards 2,2'-azino-bis-[3-ethylthiazoline-6-sulfonate] and resistance to alcoholic solvents. BRFM 66 laccase had the highest rates of dye decolourization and oxidation of nonphenolic compounds., Significance and Impact of the Study: This study identified P. coccineus and P. sanguineus as outstanding producers of high redox potential laccases, easy to purify and scale-up for industrial production. Three new laccases proved to be suitable models for white biotechnology processes and for further molecular breeding to create a new generation of tailor-made enzymes.

Neuroanatomical data show that olfactory mucosa (OM) is a possible place for interactions between nutrition and smell. A combination of differential display mRNA analysis together with a macroarray screening was developed to identify transcripts that are differentially expressed in rat OM following food deprivation. Using this method, backed on a stringent statistical analysis, we identified molecules that fell into several Gene Ontology terms including cellular and physiological process, signal transduction, and binding. Among the 15 most differentially expressed molecules, only one was upregulated, but 14 were downregulated in the fasted state among which was, unexpectedly, odorant-binding protein 1F (OBP-1F). Because of its potential relevance to olfactory physiology, we focused our further analysis on OBP-1F using in situ hybridization, quantitative polymerase chain reaction, and western blot analysis. OBP-1F was highlighted in the lateral nasal glands, but its expression (mRNA and protein) did not change following food deprivation. Only the minor fraction of OBP-1F mRNA expressed by the OM itself was downregulated following 48 h fasting. Altogether, our results suggest that the fine transcriptional control of OBP-1F in the OM following food deprivation could be efficient only at the local level, close to its site of secretion to participate in the perireceptor events of the olfactory signal reception.

In female sheep fetuses, two of the most crucial stages of ovarian development are prophase of meiosis I and follicle formation. In the present study, sheep ovaries collected on Days 25, 38, 49, 56, 67, 75, 94, and 120 of gestation, at birth, and in adulthood were tested by reverse transcription-polymerase chain reaction (RT-PCR) for the expression of 14 genes known to be involved in the ovarian differentiation in diverse organisms. The aim of this study was to determine 1) the expression pattern of six genes involved in germ cell development or meiosis (DMC1, SPO11, MSH4, MSH5, DAZL, and Boule) and five ovary-derived factors (OVOL1, SIAH2, DIAPH2, FOXL2, and FGF9), 2) the onset of gene expression for several members of the bone morphogenetic protein (BMP) pathway involved in follicular development (GDF9, BMP15, BMPR-IB), and 3) the chromosomal localization of seven of these genes in the sheep genome. The RT-PCR analysis revealed that the two germline-specific genes, DAZL and Boule, were expressed between 49 and 94 days postcoitum (dpc) with a similar pattern to typical meiosis genes (DMC1, MSH4, and MSH5), suggesting their possible participation in prophase of meiosis I. GDF9 and OVOL1 gene transcription started at 56 dpc and extended until birth, while BMP15 presented a more restricted window of expression between 94 dpc and birth, corresponding to the formation of first growing follicles. The homologous ovine genes for SPO11, DMC1, MSH5, DAZL, FGF9, DIAPH2, and SIAH2 were located on OAR 13q21-22, 3q35, 20q22, 19q13, 10q15, Xq44, and 1q41-42, respectively. In sheep, quantitative trait loci affecting female reproductive capacities are currently being detected. The ontology and precise mapping of ovarian genes will be useful to identify potential candidate genes that might underlie these effects.

In rabbit embryos, zygotic transcripts are required for the development of the embryo only from the 8- to 16-cell stage onward, more than 44 h after fertilization (i.e., zygotic gene activation; ZGA). In order to characterize the first zygotic transcripts expressed in this species we used a suppression subtractive hybridization approach to isolate RNA that was present after the major transcriptional activation (morula stage), but absent at the 1-cell stage as maternal transcripts. One hundred fourteen differentially expressed inserts were selected and sequenced. A statistical analysis of expression patterns throughout the preimplantation period of development shows that genes transcribed from ZGA onward follow different patterns of expression. Considering their early post-ZGA behavior, we describe at least two main patterns: a gradual increase from ZGA onward, and a sharp increase in expression at ZGA followed by a marked decrease at the morula stage. Our data show that both ZGA and some early post-ZGA events are involved in the establishment of specific patterns of embryonic gene expression.