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Face of first Brit revealed thanks to GEE's Professor Mark Thomas, Dr Yoan Diekmann and Natural History Museum researchers

Congratulations to Professor Mark Thomas and Dr Yoan Diekmann (both UCL Genetics, Evolution & Environment) who analysed Cheddar Man’s DNA sequences to establish aspects of his appearance. Following the Natural History Museum and Channel 4 press briefing held on 6 Febraury the story has been picked up by a number of national and international newspapers and boradcasters including the Times, Guardian, Telegraph, BBC, ITV, Sky to name but a few.

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When did flowers originate? - a new study by GEE's Professor Ziheng Yang, Dr Jose Barba-Montoya and colleagues

The study, published recently in New Phytologist by researchers from the UK and China, shows that flowering plants are neither as old as suggested by previous molecular studies, nor as young as a literal interpretation of their fossil record.

Read full article: When did flowers originate?
Read full paper: Constraining uncertainty in the timescale of angiosperm evolution and the veracity of a Cretaceous Terrestrial Revolution

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"Self-Organized Attractor Dynamics in the Developing Head Direction Circuit" - new paper by Cacucci lab

Summary: Head direction (HD) cells are neurons found in an extended cortical and subcortical network that signal the orientation of an animal’s head relative to its environment. They are a fundamental component of the wider circuit of spatially responsive hippocampal formation neurons that make up the neural cognitive map of space. During post-natal development, HD cells are the first among spatially modulated neurons in the hippocampal circuit to exhibit mature firing properties, but before eye opening, HD cell responses in rat pups have low directional information and are directionally unstable. Using Bayesian decoding of HD cell ensemble activity recorded in the anterodorsal thalamic nucleus (ADN), we characterize this instability and identify its source: under- signaling of angular head velocity, which incompletely shifts the directional signal in proportion to head turns. We find evidence that geometric cues (the corners of a square environment) can be used to mitigate this under-signaling and, thereby, stabilize the directional signal even before eye opening. Crucially, even when directional firing cannot be stabilized, ensembles of unstable HD cells show short-timescale (1–10 s) temporal and spatial couplings consistent with an adult-like HD network. The HD network is widely modeled as a continuous attractor whose output is one coherent activity peak, updated during movement by angular head velocity signals and anchored by landmark cues. Our findings present strong evidence for this model, and they demonstrate that the required network circuitry is in place and functional early during development, independent of reference to landmark information.

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"Latin Americans show wide-spread Converso ancestry and the imprint of local Native ancestry on physical appearance" - new preprint from UGI's Juan Camilo Chacón-Duque, Garrett Hellenthal, Kaustubh Adhikari, Macarena Fuentes-Guajardo, Javier Mendoza Revilla and colleagues

Abstract: Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the admixture of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods here we infer the sub-populations involved in admixture for over 6,500 Latin Americans and evaluate the impact of sub-continental ancestry on the physical appearance of these individuals. We find that pre-Columbian Native genetic structure is mirrored in Latin Americans and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that Central Andean ancestry impacts on variation of facial features in Latin Americans, particularly nose morphology, possibly relating to environmental adaptation during the evolution of Native Americans.

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Latest papers published by the Evans Lab

"The first record of albanerpetontid amphibians (Amphibia: Albanerpetontidae) from East Asia"
Abstract: Albanerpetontids are an enigmatic fossil amphibian group known from deposits of Middle Jurassic to Pliocene age. The oldest and youngest records are from Europe, but the group appeared in North America in the late Early Cretaceous and radiated there during the Late Cretaceous. Until now, the Asian record has been limited to fragmentary specimens from the Late Cretaceous of Uzbekistan. This led to speculation that albanerpetontids migrated into eastern Asia from North America in the Albian to Cenomanian interval via the Beringian land bridge. However, here we describe albanerpetontid specimens from the Lower Cretaceous Kuwajima Formation of Japan, a record that predates their first known occurrence in North America. One specimen, an association of skull and postcranial bones from a single small individual, permits the diagnosis of a new taxon. High Resolution X-ray Computed Microtomography has revealed previously unrecorded features of albanerpetontid skull morphology in three dimensions, including the presence of a supraoccipital and epipterygoids, neither of which occurs in any known lissamphibian. The placement of this new taxon within the current phylogenetic framework for Albanerpetontidae is complicated by a limited overlap of comparable elements, most notably the non-preservation of the premaxillae in the Japanese taxon. Nonetheless, phylogenetic analysis places the new taxon closer to Albanerpeton than to Anoualerpeton, Celtedens, or Wesserpeton, although Bootstrap support values are weak. The results also question the monophyly of Albanerpeton as currently defined.

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New paper from Claudio Stern’s lab in PNAS: “Neural induction by the node and placode induction by head mesoderm share an initial state resembling neural plate border and ES cells”

During development, various organ systems are set aside from the rest of the embryo as a result of “induction” from specific signalling tissues, called organizers. This paper reveals that inductions of the nervous system and of cranial sensory placodes, by different organizers, begin by the same step, which resembles the pluripotent state of embryonic stem cells. This suggests that the first event in specifying organ systems is an “erasure” of information that reverts cells back to an earlier developmental state before redirecting them to their final fate.

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BBSRC will fund project to uncover proteins and cellular processes important for ageing in fission yeast

Ageing is highly complex and affected by diverse proteins and processes. Modern biological assays can simultaneously measure properties and interactions of thousands of proteins or genes, but it is challenging to make sense of such large datasets. Advances in computational data-analysis methods, called ‘machine learning’, provide exciting opportunities to get the most from large biological datasets and thus increase our understanding of complex processes like ageing. This interdisciplinary project involving three UCL Departments, led by Jürg Bähler in collaboration with Christine Orengo and John Shawe-Taylor, will use fission yeast as a genetic model organism, together with multi-step machine learning, to comprehensively identify biological processes with fundamental importance for ageing.

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GEE's Dr Johnathan Labbadia publishes paper in Cell Reports suggesting that low levels of mitochondrial stress can have beneficial effects on protein folding and ageing

The ability to react to, and counter, the deleterious effects of protein folding stress is crucial for cells to function optimally. As cells age, the capacity to prevent protein misfolding and aggregation declines, driving cell dysfunction and tissue degeneration in adulthood. At present, little is known about the factors that regulate this phenomenon. Therefore, identifying pathways that promote or suppress protein aggregation with age could help identify new ways to maintain tissue function later in life. Using the nematode worm Caenorhabditis elegans, Labbadia and colleagues have found that low levels of mitochondrial stress early in life can suppress age-related protein misfolding in the cytosol, thereby enhancing cell robustness, and preserving tissue function with age. These effects are dependent on the conserved transcription factor HSF-1, suggesting that during times of adversity, mitochondria can communicate with the cytosolic protein quality control machinery to boost protein folding capacity and promote long-term health.

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"Gender equality from a European perspective: myth and reality" - new paper by Professor Patricia Salinas (CDB) published in Neuron

In the past 50 years, significant progress in women’s equality has been made worldwide. Western countries, particularly European countries, have implemented initiatives to attain a more gender-balanced workforce with the introduction of family friendly policies, by trying to narrow the gender pay gap and by promoting women’s career progression. In academia, however, fewer women reach top leadership positions than those in the political arena. These findings suggest that academia needs to carefully evaluate why these new policies have not been very effective. In this article, we report on the progress made in higher education, the shortcomings, and how new initiatives hold great promise for improving gender equality in academia around the globe.

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A novel strategy for ex vivo gene therapy using artificial chromosomes in human muscle stem cells published by CDB's Francesco Saverio Tedesco and colleagues in EMBO Molecular Medicine

In this new study Sara Benedetti et al. have shown that reversible immortalisation of human dystrophic muscle progenitor cells enables their genetic correction with novel human artificial chromosomes (HACs) containing the entire dystrophin genetic locus, providing evidence of translation of HAC technology for ex vivo gene therapy of Duchenne muscular dystrophy. The authors have first used lentiviral vectors to deliver specific genes to extend proliferation of different types of human skeletal muscle progenitor cells. Importantly, they have also made this process reversible. The extension of the proliferative ability of muscle cells derived from patients with Duchenne muscular dystrophy allowed their genetic correction with a novel HAC. Finally, this strategy enabled the development of a next‐generation, multifunctional HAC containing several different genes, which could be one of the largest and most complex gene therapy vectors developed to date. This exciting study has been developed in collaboration with scientists at the University of Manchester, University of Milan (Italy) and Tottori University (Japan).

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