Dataset Information

Centromere innovations within a mouse species.

ABSTRACT: Mammalian centromeres direct faithful genetic inheritance and are typically characterized by regions of highly repetitive and rapidly evolving DNA. We focused on a mouse species, Mus pahari, that we found has evolved to house centromere-specifying centromere protein-A (CENP-A) nucleosomes at the nexus of a satellite repeat that we identified and termed π-satellite (π-sat), a small number of recruitment sites for CENP-B, and short stretches of perfect telomere repeats. One M. pahari chromosome, however, houses a radically divergent centromere harboring ~6 mega-base pairs of a homogenized π-sat-related repeat, π-sat^B, that contains >20,000 functional CENP-B boxes. There, CENP-B abundance promotes accumulation of microtubule-binding components of the kinetochore and a microtubule-destabilizing kinesin of the inner centromere. We propose that the balance of pro- and anti-microtubule binding by the new centromere is what permits it to segregate during cell division with high fidelity alongside the older ones whose sequence creates a markedly different molecular composition.

SUBMITTER: Gambogi CW

PROVIDER: S-EPMC10651114 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Centromere innovations within a mouse species.

Gambogi Craig W CW Pandey Nootan N Dawicki-McKenna Jennine M JM Arora Uma P UP Liskovykh Mikhail A MA Ma Jun J Lamelza Piero P Larionov Vladimir V Lampson Michael A MA Logsdon Glennis A GA Dumont Beth L BL Black Ben E BE

Science advances 20231115 46

Mammalian centromeres direct faithful genetic inheritance and are typically characterized by regions of highly repetitive and rapidly evolving DNA. We focused on a mouse species, <i>Mus pahari,</i> that we found has evolved to house centromere-specifying centromere protein-A (CENP-A) nucleosomes at the nexus of a satellite repeat that we identified and termed π-satellite (π-sat), a small number of recruitment sites for CENP-B, and short stretches of perfect telomere repeats. One <i>M. pahari</i> ...[more]

PMID: 37967185

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Project description:BackgroundThe advanced access (AA) model has attracted much interest across Canada and worldwide as a means of ensuring timely access to health care. While nurses contribute significantly to improving access in primary healthcare, little is known about the practice changes involved in this innovative model. This study explores the experience of nurse practitioners and registered nurses with implementation of the AA model, and identifies factors that facilitate or impede change.MethodsWe used a longitudinal qualitative approach, nested within a multiple case study conducted in four university family medicine groups in Quebec that were early adopters of AA. We conducted semi-structured interviews with two types of purposively selected nurses: nurse practitioners (NPs) (n = 6) and registered nurses (RNs) (n = 5). Each nurse was interviewed twice over a 14-month period. One NP was replaced by another during the second interviews. Data were analyzed using thematic analysis based on two principles of AA and the Niezen & Mathijssen Network Model (2014).ResultsOver time, RNs were not able to review the appointment system according to the AA philosophy. Half of NPs managed to operate according to AA. Regarding collaborative practice, RNs were still struggling to participate in team-based care. NPs were providing independent and collaborative patient care in both consultative and joint practice, and were assuming leadership in managing patients with acute and chronic diseases. Thematic analysis revealed influential factors at the institutional, organizational, professional, individual and patient level, which acted mainly as facilitators for NPs and barriers for RNs. These factors were: 1) policy and legislation; 2) organizational policy support (leadership and strategies to support nurses' practice change); facility and employment arrangements (supply and availability of human resources); Inter-professional collegiality; 3) professional boundaries; 4) knowledge and capabilities; and 5) patient perceptions.ConclusionsOur findings suggest that healthcare decision-makers and organizations need to redefine the boundaries of each category of nursing practice within AA, and create an optimal professional and organizational context that supports practice transformation. They highlight the need to structure teamwork efficiently, and integrate and maximize nurses' capacities within the team throughout AA implementation in order to reduce waiting times.

Dataset Information

Centromere innovations within a mouse species.

Publications

Centromere innovations within a mouse species.

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