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Organizational workforces are becoming increasingly dispersed. To facilitate communications among individuals or groups of people located in a number of different locations, teleconferencing technologies, such as audioconferencing, have been developed. The authors examined whether a structural group intervention, the stepladder technique, can facilitate the task performance of 4-person groups (n = 52) when using audioconferencing. Consistent with research conducted on face-to-face groups, the stepladder technique was found to facilitate the decision-making performance of groups interacting via audioconference. The authors postulated that certain structural elements of the stepladder technique compensate for obstacles inherent in nonvisual communications. Supplementary analyses examined best member influence and the existence of order of entry effects into the stepladder process.

Telomere dysfunction may result in chromosomal abnormalities, DNA damage responses, and even cancer. Early studies in lower organisms have helped to establish the crucial role of telomerase and telomeric proteins in maintaining telomere length and protecting telomere ends. In Oxytricha nova, telomere G-overhangs are protected by the TEBP-α/β heterodimer. Human telomeres contain duplex telomeric repeats with 3′ single-stranded G-overhangs, and may fold into a t-loop structure that helps to shield them from being recognized as DNA breaks. Additionally, the TEBP-α homologue, POT1, which binds telomeric single-stranded DNA (ssDNA), associates with multiple telomeric proteins (for example, TPP1, TIN2, TRF1, TRF2 and RAP1) to form the six-protein telosome/shelterin and other subcomplexes. These telomeric protein complexes in turn interact with diverse pathways to form the telomere interactome for telomere maintenance. However, the mechanisms by which the POT1-containing telosome communicates with telomerase to regulate telomeres remain to be elucidated. Here we demonstrate that TPP1 is a putative mammalian homologue of TEBP-β and contains a predicted amino-terminal oligonucleotide/oligosaccharide binding (OB) fold. TPP1–POT1 association enhanced POT1 affinity for telomeric ssDNA. In addition, the TPP1 OB fold, as well as POT1–TPP1 binding, seemed critical for POT1-mediated telomere-length control and telomere-end protection in human cells. Disruption of POT1–TPP1 interaction by dominant negative TPP1 expression or RNA interference (RNAi) resulted in telomere-length alteration and DNA damage responses. Furthermore, we offer evidence that TPP1 associates with the telomerase in a TPP1-OB-fold-dependent manner, providing a physical link between telomerase and the telosome/shelterin complex. Our findings highlight the critical role of TPP1 in telomere maintenance, and support a yin–yang model in which TPP1 and POT1 function as a unit to protect human telomeres, by both positively and negatively regulating telomerase access to telomere DNA. [ABSTRACT FROM AUTHOR]

We describe here a simple method to enrich mitochondrial fractions from mammalian cells for downstream analyses in the lab. Mitochondria purification involves cell lysis followed by separation of the organelles from the rest of the cellular components. Here, we use detergent to rupture the cell membrane of mammalian cells followed by differential centrifugation to enrich the organelles. Optimum conditions with respect to detergent concentration, time, sample size, and yield are discussed. The method's utility in downstream analyses and ease of processing multiple samples simultaneously is also described. All the reagents in this method can be assembled in-house, are economical, and are comparable, if not superior, to commercially available kits in terms of mitochondrial yield and integrity. • Rapid enrichment of mitochondria from mammalian cells using commonly available reagents. • Multiple samples can be processed simultaneously. • Works over a wide range of sample size (1 million to 100 million cells)., (© 2020 The Authors. Published by Elsevier B.V.)

The Notch pathway is a signaling network essential for proper organ development in an embryo, and is indispensable for tissue regeneration in the adult. This key regulatory signaling network is evolutionarily conserved in all metazoans and is continually utilized for the building, maintenance and repair of diverse organs and tissues. Importantly, dysfunctions in the Notch pathway have been demonstrated to result in oncogenic transformation, such as in lymphoid cancers, and have been linked to the pathogenesis of several inherited human diseases. Therefore, the ability to regulate Notch signaling intensity both positively and negatively has a very high therapeutic relevance. Adapting this pathway for tissue engineering applications has great potential to spear-head the development of smart biomaterials to deliberately control cell-fate decisions and lead to designer ex vivo morphogenesis. This review describes the components of Notch-specific signal transduction, presents the role of the Notch signaling network in constructing and repairing multiple organ systems, summarizes the Notch-related pathologies, outlines current advances in the deliberate modulation of the Notch pathway in bioengineering applications, and introduces future perspectives on the use of Notch pathway manipulations as a powerful universal tool in tissue engineering and in the orchestration of stem cell responses. This review also summarizes the existing bioengineering methods most suitable for the deliberate manipulation of Notch signaling, such as smart biomaterials able to pattern Notch ligands or to create gradients of Notch agonists and antagonists. Such methods will likely facilitate the engineering and dynamic remodeling of tissues composed of stem, progenitor and differentiated cells derived from an initially equivalent cell population.

Telomere dysfunction may result in chromosomal abnormalities, DNA damage responses, and even cancer. Early studies in lower organisms have helped to establish the crucial role of telomerase and telomeric proteins in maintaining telomere length and protecting telomere ends. In Oxytricha nova, telomere G-overhangs are protected by the TEBP-alpha/beta heterodimer. Human telomeres contain duplex telomeric repeats with 3' single-stranded G-overhangs, and may fold into a t-loop structure that helps to shield them from being recognized as DNA breaks. Additionally, the TEBP-alpha homologue, POT1, which binds telomeric single-stranded DNA (ssDNA), associates with multiple telomeric proteins (for example, TPP1, TIN2, TRF1, TRF2 and RAP1) to form the six-protein telosome/shelterin and other subcomplexes. These telomeric protein complexes in turn interact with diverse pathways to form the telomere interactome for telomere maintenance. However, the mechanisms by which the POT1-containing telosome communicates with telomerase to regulate telomeres remain to be elucidated. Here we demonstrate that TPP1 is a putative mammalian homologue of TEBP-beta and contains a predicted amino-terminal oligonucleotide/oligosaccharide binding (OB) fold. TPP1-POT1 association enhanced POT1 affinity for telomeric ssDNA. In addition, the TPP1 OB fold, as well as POT1-TPP1 binding, seemed critical for POT1-mediated telomere-length control and telomere-end protection in human cells. Disruption of POT1-TPP1 interaction by dominant negative TPP1 expression or RNA interference (RNAi) resulted in telomere-length alteration and DNA damage responses. Furthermore, we offer evidence that TPP1 associates with the telomerase in a TPP1-OB-fold-dependent manner, providing a physical link between telomerase and the telosome/shelterin complex. Our findings highlight the critical role of TPP1 in telomere maintenance, and support a yin-yang model in which TPP1 and POT1 function as a unit to protect human telomeres, by both positively and negatively regulating telomerase access to telomere DNA.