Vimentin intermediate filaments modulate cell traction force but not cell sensitivity to substrate stiffness.

The ability of cells to sense and respond to the mechanical stiffness of the surrounding matrix is important to support normal cell function, wound healing, and development. Central to the process of durosensing is the cytoskeleton composed of three classes of filaments: F-actin, microtubules, and intermediate filaments (IFs). Vimentin is an IF protein that contributes significantly to cell mechanics and cell traction force, which is required to probe extracellular matrix.

Expression and differentiation between OCT4A and its Pseudogenes in human ESCs and differentiated adult somatic cells.

The POU5F1 gene codes for the OCT4 transcription factor, which is one of the key regulators of pluripotency. Its transcription, alternative splicing, and alternative translation leading to the synthesis of the active, nuclear localized OCT4A has been described in detail. Much less, however, is known about actively transcribed OCT4 pseudogenes, several of which display high homology to OCT4A and can be expressed and translated into proteins.

Maintenance of multipotency in human dermal fibroblasts treated with Xenopus laevis egg extract requires exogenous fibroblast growth factor-2.

Direct reprogramming of a differentiated somatic cell into a developmentally more plastic cell would offer an alternative to applications in regenerative medicine that currently depend on either embryonic stem cells (ESCs), adult stem cells, or induced pluripotent stem cells (iPSCs). Here we report the potential of select Xenopus laevis egg extract fractions, in combination with exogenous fibroblast growth factor-2 (FGF2), to affect life span, morphology, gene expression, protein translation, and cellular localization of OCT4 and NANOG transcription factors, and the developmental potential of human dermal fibroblasts in vitro. A gradual change in morphology is accompanied by translation of embryonic transcription factors and their nuclear localization and a life span exceeding 60 population doublings.

FGF2-induced effects on transcriptome associated with regeneration competence in adult human fibroblasts.

Background: Adult human fibroblasts grown in low oxygen and with FGF2 supplementation have the capacity to tip the healing outcome of skeletal muscle injury - by favoring regeneration response in vivo over scar formation. Here, we compare the transcriptomes of control adult human dermal fibroblasts and induced regeneration-competent (iRC) fibroblasts to identify transcriptional changes that may be related to their regeneration competence.

Results: We identified a unique gene-expression profile that characterizes FGF2-induced iRC fibroblast phenotype.

Identification of novel microRNAs in Xenopus laevis metaphase II arrested eggs.

Using a combination of deep sequencing and bioinformatics approach, we for the first time identify miRNAs and their relative abundance in mature, metaphase II arrested eggs in Xenopus laevis. We characterize 115 miRNAs that have been described either in Xenopus tropicalis (85), X. laevis (9), or other vertebrate species (21) that also map to known Xenopus pre-miRNAs and to the X.