<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-04-17T01:09:30Z</responseDate><request verb="GetRecord" identifier="oai:www.recercat.cat:2445/122640" metadataPrefix="marc">https://recercat.cat/oai/request</request><GetRecord><record><header><identifier>oai:recercat.cat:2445/122640</identifier><datestamp>2025-12-04T22:49:46Z</datestamp><setSpec>com_2072_1057</setSpec><setSpec>col_2072_478825</setSpec><setSpec>col_2072_478909</setSpec><setSpec>col_2072_478917</setSpec></header><metadata><record xmlns="http://www.loc.gov/MARC21/slim" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://www.loc.gov/MARC21/slim http://www.loc.gov/standards/marcxml/schema/MARC21slim.xsd">
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      <subfield code="a">Calvo Martín, Juan Manuel</subfield>
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      <subfield code="a">Papaceit Vidal, Montserrat</subfield>
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      <subfield code="a">Segarra Robert, Carmen</subfield>
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      <subfield code="c">2018-05-29T13:59:20Z</subfield>
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      <subfield code="c">2018-05-29T13:59:20Z</subfield>
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      <subfield code="c">2017-09-14</subfield>
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      <subfield code="c">2018-05-29T13:59:20Z</subfield>
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      <subfield code="a">Polycomb group (PcG) proteins are important regulatory factors that modulate the chromatin state. They form protein complexes that repress gene expression by the introduction of posttranslational histone modifications. The study of PcG proteins divergence in Drosophila revealed signals of coevolution among them and an acceleration of the nonsynonymous evolutionary rate in the lineage ancestral to the obscura group species, mainly in subunits of the Pcl-PRC2 complex. Herein, we have studied the nucleotide polymorphism of PcG genes in a natural population of D. subobscura to detect whether natural selection has also modulated the evolution of these important regulatory genes in a more recent time scale. Results show that most genes are under the action of purifying selection and present a level and pattern of polymorphism consistent with predictions of the neutral model, the exceptions being Su(z)12 and Pho. MK tests indicate an accumulation of adaptive changes in the SU(Z)12 protein during the divergence of D. subobscura and D. guanche. In contrast, the HKA test shows a deficit of polymorphism at Pho. The most likely explanation for this reduced variation is the location of this gene in the dot-like chromosome and would indicate that this chromosome also has null or very low recombination in D. subobscura, as reported in D. melanogaster.</subfield>
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      <subfield code="a">Drosòfila subobscura</subfield>
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      <subfield code="a">Mapatge cromosòmic humà</subfield>
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      <subfield code="a">Genètica molecular</subfield>
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      <subfield code="a">Drosophila subobscura</subfield>
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      <subfield code="a">Human gene mapping</subfield>
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      <subfield code="a">Molecular genetics</subfield>
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      <subfield code="a">Molecular population genetics of the Polycomb genes in Drosophila subobscura</subfield>
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