8 research outputs found
Linkage map construction involving a reciprocal translocation
This paper is concerned with a novel statistical–genetic approach for the construction of linkage maps in populations obtained from reciprocal translocation heterozygotes of barley (Hordeum vulgare L.). Using standard linkage analysis, translocations usually lead to ‘pseudo-linkage’: the mixing up of markers from the chromosomes involved in the translocation into a single linkage group. Close to the translocation breakpoints recombination is severely suppressed and, as a consequence, ordering markers in those regions is not feasible. The novel strategy presented in this paper is based on (1) disentangling the “pseudo-linkage” using principal coordinate analysis, (2) separating individuals into translocated types and normal types and (3) separating markers into those close to and those more distant from the translocation breakpoints. The methods make use of a consensus map of the species involved. The final product consists of integrated linkage maps of the distal parts of the chromosomes involved in the translocation
Marine mammals and Good Environmental Status: Science, Policy and Society; Challenges and Opportunities
The Marine Strategy Framework Directive has become the key instrument for marine conservation in European seas. We review its implementation, focusing on cetacean biodiversity, using
the examples of Spain and the Regional Seas Convention, OSPAR. The MSFD has been widely criticised for legal vagueness, lack of coordination,
uncertainty about funding, and poor governance; its
future role within EU Integrated Maritime Policy
remains unclear. Nevertheless, the first stages of the
process have run broadly to schedule: current status,
environmental objectives and indicators have been
described and the design of monitoring programmes is in progress, drawing on experience with other environmental
legislation. The MSFD is now entering its
critical phase, with lack of funding for monitoring,
limited scope for management interventions, and
uncertainty about how conservation objectives will
be reconciled with the needs of other marine and
maritime sectors, being among the main concerns.
Clarity in governance, about the roles of the EU,
Member States, Regional Seas Conventions and
stakeholders, is needed to ensure success. However,
even if (as seems likely) good environmental status
cannot be achieved by 2020, significant steps will have been taken to place environmental sustainability
centre-stage in the development of Integrated Maritime
Policy for EU seas.Postprin
Diagnosis of atlanto-occipital dissociation: Standardised measurements of normal craniocervical relationship in finless porpoises (genus Neophocaena) using postmortem computed tomography
Normal computed tomographic features and reference values for the coelomic cavity in pet parrots
Enoxacin degradation by photo-Fenton process combined with a biological treatment: optimization and improvement of by-products biodegradability
A methyl transferase links the circadian clock to the regulation of alternative splicing
Circadian rhythms allow organisms to time biological processes to the most appropriate phases of the day–night cycle1. Post-transcriptional regulation is emerging as an important component of circadian networks2, 3, 4, 5, 6, but the molecular mechanisms linking the circadian clock to the control of RNA processing are largely unknown. Here we show that PROTEIN ARGININE METHYL TRANSFERASE 5 (PRMT5), which transfers methyl groups to arginine residues present in histones7 and Sm spliceosomal proteins8, 9, links the circadian clock to the control of alternative splicing in plants. Mutations in PRMT5 impair several circadian rhythms in Arabidopsis thaliana and this phenotype is caused, at least in part, by a strong alteration in alternative splicing of the core-clock gene PSEUDO RESPONSE REGULATOR 9 (PRR9). Furthermore, genome-wide studies show that PRMT5 contributes to the regulation of many pre-messenger-RNA splicing events, probably by modulating 5′-splice-site recognition. PRMT5 expression shows daily and circadian oscillations, and this contributes to the mediation of the circadian regulation of expression and alternative splicing of a subset of genes. Circadian rhythms in locomotor activity are also disrupted in dart5-1, a mutant affected in the Drosophila melanogaster PRMT5 homologue, and this is associated with alterations in splicing of the core-clock gene period and several clock-associated genes. Our results demonstrate a key role for PRMT5 in the regulation of alternative splicing and indicate that the interplay between the circadian clock and the regulation of alternative splicing by PRMT5 constitutes a common mechanism that helps organisms to synchronize physiological processes with daily changes in environmental conditions