27 research outputs found
Promoter keyholes enable specific and persistent multi-gene expression programs in primary T cells without genome modification
Non-invasive epigenome editing is a promising strategy for engineering gene expression programs, yet potency, specificity, and persistence remain challenging. Here we show that effective epigenome editing is gated at single-base precision via 'keyhole' sites in endogenous regulatory DNA. Synthetic repressors targeting promoter keyholes can ablate gene expression in up to 99% of primary cells with single-gene specificity and can seamlessly repress multiple genes in combination. Transient exposure of primary T cells to keyhole repressors confers mitotically heritable silencing that persists to the limit of primary cultures in vitro and for at least 4 weeks in vivo, enabling manufacturing of cell products with enhanced therapeutic efficacy. DNA recognition and effector domains can be encoded as separate proteins that reassemble at keyhole sites and function with the same efficiency as single chain effectors, enabling gated control and rapid screening for novel functional domains that modulate endogenous gene expression patterns. Our results provide a powerful and exponentially flexible system for programming gene expression and therapeutic cell products
Promoter keyholes enable specific and persistent multi-gene expression programs in primary T cells without genome modification
Non-invasive epigenome editing is a promising strategy for engineering gene expression programs, yet potency, specificity, and persistence remain challenging. Here we show that effective epigenome editing is gated at single-base precision via 'keyhole' sites in endogenous regulatory DNA. Synthetic repressors targeting promoter keyholes can ablate gene expression in up to 99% of primary cells with single-gene specificity and can seamlessly repress multiple genes in combination. Transient exposure of primary T cells to keyhole repressors confers mitotically heritable silencing that persists to the limit of primary cultures in vitro and for at least 4 weeks in vivo, enabling manufacturing of cell products with enhanced therapeutic efficacy. DNA recognition and effector domains can be encoded as separate proteins that reassemble at keyhole sites and function with the same efficiency as single chain effectors, enabling gated control and rapid screening for novel functional domains that modulate endogenous gene expression patterns. Our results provide a powerful and exponentially flexible system for programming gene expression and therapeutic cell products
Roles of DNA polymerase I in leading and lagging-strand replication defined by a high-resolution mutation footprint of ColE1 plasmid replication
DNA polymerase I (pol I) processes RNA primers during lagging-strand synthesis and fills small gaps during DNA repair reactions. However, it is unclear how pol I and pol III work together during replication and repair or how extensive pol I processing of Okazaki fragments is in vivo. Here, we address these questions by analyzing pol I mutations generated through error-prone replication of ColE1 plasmids. The data were obtained by direct sequencing, allowing an accurate determination of the mutation spectrum and distribution. Pol I’s mutational footprint suggests: (i) during leading-strand replication pol I is gradually replaced by pol III over at least 1.3 kb; (ii) pol I processing of Okazaki fragments is limited to ∼20 nt and (iii) the size of Okazaki fragments is short (∼250 nt). While based on ColE1 plasmid replication, our findings are likely relevant to other pol I replicative processes such as chromosomal replication and DNA repair, which differ from ColE1 replication mostly at the recruitment steps. This mutation footprinting approach should help establish the role of other prokaryotic or eukaryotic polymerases in vivo, and provides a tool to investigate how sequence topology, DNA damage, or interactions with protein partners may affect the function of individual DNA polymerases
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Assessing the impacts of 1.5 °C global warming – simulation protocol of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP2b)
In Paris, France, December 2015, the Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) invited the Intergovernmental Panel on Climate Change (IPCC) to provide a "special report in 2018 on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways". In Nairobi, Kenya, April 2016, the IPCC panel accepted the invitation. Here we describe the response devised within the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) to provide tailored, cross-sectorally consistent impact projections to broaden the scientific basis for the report. The simulation protocol is designed to allow for (1) separation of the impacts of historical warming starting from pre-industrial conditions from impacts of other drivers such as historical land-use changes (based on pre-industrial and historical impact model simulations); (2) quantification of the impacts of additional warming up to 1.5°C, including a potential overshoot and long-term impacts up to 2299, and comparison to higher levels of global mean temperature change (based on the low-emissions Representative Concentration Pathway RCP2.6 and a no-mitigation pathway RCP6.0) with socio-economic conditions fixed at 2005 levels; and (3) assessment of the climate effects based on the same climate scenarios while accounting for simultaneous changes in socio-economic conditions following the middle-of-the-road Shared Socioeconomic Pathway (SSP2, Fricko et al., 2016) and in particular differential bioenergy requirements associated with the transformation of the energy system to comply with RCP2.6 compared to RCP6.0. With the aim of providing the scientific basis for an aggregation of impacts across sectors and analysis of cross-sectoral interactions that may dampen or amplify sectoral impacts, the protocol is designed to facilitate consistent impact projections from a range of impact models across different sectors (global and regional hydrology, lakes, global crops, global vegetation, regional forests, global and regional marine ecosystems and fisheries, global and regional coastal infrastructure, energy supply and demand, temperature-related mortality, and global terrestrial biodiversity)
An examination of the language construct in NIMH's research domain criteria:Time for reconceptualization!
The National Institute of Mental Health’s Research Domain
Criteria (RDoC) Initiative “calls for the development of new ways of classifying psychopathology
based on dimensions of observable behavior.” As aresult of this ambitious initiative, language has
been identifi d as an independent construct in the RDoC matrix. In this article, we frame language
within an evolutionary and neuro- psychological context and discuss some of the limitations to the
current measurements of language. Findings from genomics and the neuroimaging of performance during
language tasks are dis- cussed in relation to serious mental illness and within the context of
caveats regarding measuring language. Indeed, the data collec- tion and analysis methods employed
to assay language have been both aided and constrained by the available technologies,
methodologies, and conceptual defi Consequently, differ- ent fields of language research
show inconsistent defi s of language that have become increasingly broad over time. Individ- ually,
they have also shown significant improvements in conceptual resolution, aswell as inexperimental
and analytic techniques. More recently, language research has embraced collaborations across
disciplines, notably neuroscience, cognitive science, and computa- tional linguistics and has
ultimately re-defi classical ideas of language. As we move forward, the new models of language with
their remarkably multifaceted constructs force a re-examination of the NIMH RDoC conceptualization
of language and thus the
neuroscience and genetics underlying this concept
dOCRL maintains immune cell quiescence in Drosophila by regulating endosomal traffic
Lowe Syndrome is a developmental disorder characterized by eye, kidney, and neurological pathologies, and is caused by mutations in the phosphatidylinositol-5-phosphatase OCRL. OCRL plays diverse roles in endocytic and endolysosomal trafficking, cytokinesis, and ciliogenesis, but it is unclear which of these cellular functions underlie specific patient symptoms. Here, we show that mutation of Drosophila OCRL causes cell-autonomous activation of hemocytes, which are macrophage-like cells of the innate immune system. Among many cell biological defects that we identified in docrl mutant hemocytes, we pinpointed the cause of innate immune cell activation to reduced Rab11-dependent recycling traffic and concomitantly increased Rab7-dependent late endosome traffic. Loss of docrl amplifies multiple immune-relevant signals, including Toll, Jun kinase, and STAT, and leads to Rab11-sensitive mis-sorting and excessive secretion of the Toll ligand Spåtzle. Thus, docrl regulation of endosomal traffic maintains hemocytes in a poised, but quiescent state, suggesting mechanisms by which endosomal misregulation of signaling may contribute to symptoms of Lowe syndrome
Sonic Hedgehog upregulation does not enhance the survival and engraftment of stem cell-derived cardiomyocytes in infarcted hearts.
The engraftment of human stem cell-derived cardiomyocytes (hSC-CMs) is a promising treatment for remuscularizing the heart wall post-infarction, but it is plagued by low survival of transplanted cells. We hypothesize that this low survival rate is due to continued ischemia within the infarct, and that increasing the vascularization of the scar will ameliorate the ischemia and improve hSC-CM survival and engraftment. An adenovirus expressing the vascular growth factor Sonic Hedgehog (Shh) was injected into the infarcted myocardium of rats immediately after ischemia/reperfusion, four days prior to hSC-CM injection. By two weeks post-cell injection, Shh treatment had successfully increased capillary density outside the scar, but not within the scar. In addition, there was no change in vessel size or percent vascular volume when compared to cell injection alone. Micro-computed tomography revealed that Shh failed to increase the number and size of larger vessels. It also had no effect on graft size or heart function when compared to cell engraftment alone. Our data suggests that, when combined with the engraftment of hSC-CMs, expression of Shh within the infarct scar and surrounding myocardium is unable to increase vascularization of the infarct scar, and it does not improve survival or function of hSC-CM grafts
Efficient generation and cryopreservation of cardiomyocytes derived from human embryonic stem cells
Dinamička neuromišićna stabilizacija (DNS) je metoda koja obuhvaća principe razvojne kineziologije te se moţe koristi u tretiranju slabinskih bolnih sindroma. Njezin osnivač je profesor i fizioterapeut Pavel Kolar. Uz razvojne poloţaje tj. vjeţbe, bitno je usvojiti neka osnovna načela DNS-a kako bi izvedba bila cjelokupna. Više od 80% osoba barem jednom u svom ţivotu osjeti bol u slabinskom dijelu kraljeţnice, a bol koja nastane u 90% slučajeva je posljedica nekog mehaničkog djelovanja. Ovakvim pristupom vjeţbanja ţeli se postići optimalna stabilizaciju trupa i nesmetano kretanje kako tijela tako i ekstremiteta, uz pravovremenu predaktivaciju trupa. Svaki razvojni poloţaj je i vjeţba te ima svoju progresivnu i regresivnu fazu.Dynamic neuromuscular stabilization (DNS) is a method that includes the principles of development kinesiology and it can be used for the treatment of lumbar painful syndromes. Her founder is Professor and Physiotherapist Pavel Kolar. With developmental positions, ie exercises, it is essential to adopt some basic DNS principles to make the overall performance. More than 80% of people at least once in their life experience pain in the lumbar part, and the disease that occurs in 90% of cases is the result of some mechanical action. With this approach, the exercise aims to achieve optimum body stabilization and smooth movements of both the body and the extremities, with timely pre-activation of the core. Each different position is a exercise and has its own progressive and regressive phase
Correction to: Optical mapping of human embryonic stem cell-derived cardiomyocyte graft electrical activity in injured hearts
An amendment to this paper has been published and can be accessed via the original article