T cell receptor (TCR) gene therapy is an effective cancer treatment. Ideally, the TCR should be of human origin and have optimal avidity, e.g.
View Article and Find Full Text PDFThe CRISPR/Cas9 system is a powerful tool for gene repair that holds great potential for gene therapy to cure monogenic diseases. Despite intensive improvement, the safety of this system remains a major clinical concern. In contrast to Cas9 nuclease, Cas9 nickases with a pair of short-distance (38-68 bp) PAM-out single-guide RNAs (sgRNAs) preserve gene repair efficiency while strongly reducing off-target effects.
View Article and Find Full Text PDFConserv Physiol
October 2022
Juvenile fall-run Chinook salmon () in the Sacramento-San Joaquin River Basin experience temporally and spatially heterogenous temperature regimes, between cool upper tributaries and the warm channelized Delta, during freshwater rearing and outmigration. Limited water resources necessitate human management of dam releases, allowing temperature modifications. The objective of this study was to examine the effect of temperature on specific dynamic action (SDA), or the metabolic cost associated with feeding and digestion, which is thought to represent a substantial portion of fish energy budgets.
View Article and Find Full Text PDFWhile CRISPR-Cas9 is key for the development of gene therapy, its potential off-target mutations are still a major concern. Here, we establish a "spacer-nick" gene correction approach that combines the Cas9 nickase with a pair of PAM-out sgRNAs at a distance of 200 to 350 bp. In combination with adeno-associated virus (AAV) serotype 6 template delivery, our approach led to efficient HDR in human hematopoietic stem and progenitor cells (HSPCs including long-term HSCs) and T cells, with minimal NHEJ-mediated on-target mutations.
View Article and Find Full Text PDFPrecision genomic alterations largely rely on homology directed repair (HDR), but targeting without homology using the non-homologous end-joining (NHEJ) pathway has gained attention as a promising alternative. Previous studies demonstrated precise insertions formed by the ligation of donor DNA into a targeted genomic double-strand break in both dividing and non-dividing cells. Here, we demonstrate the use of NHEJ repair to genomic segments with donor sequences; we name this method 'Replace' editing (ational nd-joining rotocol deivering targeted sequene xchange).
View Article and Find Full Text PDFProc Biol Sci
October 2020
A warming climate poses a fundamental problem for embryos that develop within eggs because their demand for oxygen (O) increases much more rapidly with temperature than their capacity for supply, which is constrained by diffusion across the egg surface. Thus, as temperatures rise, eggs may experience O limitation due to an imbalance between O supply and demand. Here, we formulate a mathematical model of O limitation and experimentally test whether this mechanism underlies the upper thermal tolerance in large aquatic eggs.
View Article and Find Full Text PDFEarly developmental stages of fishes are particularly sensitive to changes in environmental variables that affect physiological processes such as metabolism and growth. Both temperature and food availability have significant effects on the growth and survival of larval and juvenile fishes. As climate change and anthropogenic disturbances influence sensitive rearing environments of fishes it is unlikely that they will experience changes in temperature or food availability in isolation.
View Article and Find Full Text PDFHuman induced pluripotent stem cells (hiPSCs) represent an ideal in vitro platform to study human genetics and biology. The recent advent of programmable nucleases makes also the human genome amenable to experimental genetics through either the correction of mutations in patient-derived iPSC lines or the de novo introduction of mutations into otherwise healthy iPSCs. The production of specific and sometimes complex genotypes in multiple cell lines requires efficient and streamlined gene editing technologies.
View Article and Find Full Text PDFDNA double-strand breaks (DSBs) are produced intentionally by RNA-guided nucleases to achieve genome editing through DSB repair. These breaks are repaired by one of two main repair pathways, classic non-homologous end joining (c-NHEJ) and homology-directed repair (HDR), the latter being restricted to the S/G2 phases of the cell cycle and notably less frequent. Precise genome editing applications rely on HDR, with the abundant c-NHEJ formed mutations presenting a barrier to achieving high rates of precise sequence modifications.
View Article and Find Full Text PDFFish, even of the same species, can exhibit substantial variation in energy density (energy per unit wet weight). Most of this variation is due to differences in the amount of storage lipids. In addition to their importance as energy reserves for reproduction and for survival during unfavourable conditions, the accumulation of lipids represents a large energetic flux for many species, so figuring out how this energy flux is integrated with other major energy fluxes (growth, reproduction) is critical for any general theory of organismal energetics.
View Article and Find Full Text PDFPredicting species responses to climate change is a central challenge in ecology. These predictions are often based on lab-derived phenomenological relationships between temperature and fitness metrics. We tested one of these relationships using the embryonic stage of a Chinook salmon population.
View Article and Find Full Text PDFJ R Soc Interface
December 2015
Marine mussels of the genus Mytilus live in the hostile intertidal zone, attached to rocks, bio-fouled surfaces and each other via collagen-rich threads ending in adhesive pads, the plaques. Plaques adhere in salty, alkaline seawater, withstanding waves and tidal currents. Each plaque requires a force of several newtons to detach.
View Article and Find Full Text PDFThe biochemistry of mussel adhesion has inspired the design of surface primers, adhesives, coatings and gels for technological applications. These mussel-inspired systems often focus on incorporating the amino acid 3,4-dihydroxyphenyl-L-alanine (Dopa) or a catecholic analog into a polymer. Unfortunately, effective use of Dopa is compromised by its susceptibility to auto-oxidation at neutral pH.
View Article and Find Full Text PDFSessile marine mussels must "dry" underwater surfaces before adhering to them. Synthetic adhesives have yet to overcome this fundamental challenge. Previous studies of bioinspired adhesion have largely been performed under applied compressive forces, but such studies are poor predictors of the ability of an adhesive to spontaneously penetrate surface hydration layers.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2013
The adhesion of mussel foot proteins (Mfps) to a variety of specially engineered mineral and metal oxide surfaces has previously been investigated extensively, but the relevance of these studies to adhesion in biological environments remains unknown. Most solid surfaces exposed to seawater or physiological fluids become fouled by organic conditioning films and biofilms within minutes. Understanding the binding mechanisms of Mfps to organic films with known chemical and physical properties therefore is of considerable theoretical and practical interest.
View Article and Find Full Text PDFMussel foot proteins (mfps) have been investigated as a source of inspiration for the design of underwater coatings and adhesives. Recent analysis of various mfps by a surface forces apparatus (SFA) revealed that mfp-1 functions as a coating, whereas mfp-3 and mfp-5 resemble adhesive primers on mica surfaces. To further refine and elaborate the surface properties of mfps, the force-distance profiles of the interactions between thin mfp (i.
View Article and Find Full Text PDFMussels have a remarkable ability to attach their holdfast, or byssus, opportunistically to a variety of substrata that are wet, saline, corroded, and/or fouled by biofilms. Mytilus edulis foot protein-5 (Mefp-5) is one of several proteins in the byssal adhesive plaque of the mussel M. edulis.
View Article and Find Full Text PDFNat Chem Biol
July 2011
Mussel adhesion is mediated by foot proteins (mfps) rich in a catecholic amino acid, 3,4-dihydroxyphenylalanine (dopa), capable of forming strong bidentate interactions with a variety of surfaces. A tendency toward facile auto-oxidation, however, often renders dopa unreliable for adhesion. We demonstrate that mussels limit dopa oxidation during adhesive plaque formation by imposing an acidic, reducing regime based on the thiol-rich mfp-6, which restores dopa by coupling the oxidation of thiols to dopaquinone reduction.
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