Posts Tagged: biology

How do harmful chronic myelogenous leukemia stem cells obtain their nutrients?

How do harmful chronic myelogenous leukemia stem cells obtain their nutrients?

Applicability of a new strategy to overcome disease recurrence in patients with chronic myelogenous leukemia     A research group in Japan and in Korea has found a novel nutrient uptake process that maintains the activity of murine chronic myelogenous leukemia (CML) stem cells. Pharmacological inhibition of nutrient uptake decreased CML stem cell activity in vivo. Based on a report published on August 20, 2015 in┬áNature Communications, it has been established that certain nutrients support CML stem cell activity in vivo, thus pointing towards a potential therapeutic target for CML therapy. CML stem cells, the cellular source of a vast majority of CML cells, are reportedly responsible for the recurrence… Read more

Protein machines make fluctuating flows unconsciously

Protein machines make fluctuating flows unconsciously

An international research group has demonstrated that protein machines, regardless of their specific functions, can collectively induce fluctuating hydrodynamic flows and substantially enhance the diffusive motions of particles in the cell. Biological cells contain large numbers of active proteins that repeatedly change their conformations. These protein machines have a variety of specific functions, acting as motors, ion pumps, or enzymes, and they need a supply of ATP or other substrates to maintain their cyclic operation. Professor Alexander S. Mikhailov (Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, and Research Center for the Mathematics on Chromatin Live Dynamics [RcMcD] at Hiroshima University) and Professor Raymond Kapral (Department… Read more

New molecular mechanism of neuropathic pain in mice

New molecular mechanism of neuropathic pain in mice

  The downregulation of spinal astrocyte connexin43 (Cx43) expression causes sustained neuropathic pain following peripheral nerve injury. The inflammatory cytokine tumor necrosis factor (TNF) mediates the downregulation of Cx43 expression, which leads to decreased expression of the glutamate transporter GLT-1 and enhanced glutamatergic neurotransmission. Targeting the recovery of Cx43 function using pharmacological approaches or gene therapy might serve as novel therapeutic strategies ameliorate neurological disorders in general and neuropathic pain in particular. Spinal cord astrocytes are critical in the maintenance of neuropathic pain. Cx43 expressed on spinal dorsal horn astrocytes modulates synaptic neurotransmission, but its role in nociceptive transduction has yet to be fully elaborated. Several types of Cx have… Read more

Simultaneous live imaging of a specific gene’s transcription and dynamics

Simultaneous live imaging of a specific gene’s transcription and dynamics

The Real-time Observation of Localization and EXpression (ROLEX) system   Dr. Hiroshi Ochiai and his colleagues, Dr. Takeshi Sugawara (Research Center for the Mathematics on Chromatin Live Dynamics [RcMcD] at Hiroshima University) and Professor Takashi Yamamoto (Graduate School of Science at Hiroshima University), have established a novel live-imaging method termed the “Real-time Observation of Localization and EXpression (ROLEX)” system. This system enables simultaneous measurements of the transcriptional activity and nuclear position of endogenous genes using MS2 transcription imaging and clustered regularly interspaced short palindromic repeats (CRISPR) gene-imaging techniques.   Dr. Ochiai stated, “By using only existing techniques, such as the chromatin conformation capture (3C)-related method and fluorescence in situ hybridization… Read more

What are the mechanisms of zooxanthella expulsion from coral?

What are the mechanisms of zooxanthella expulsion from coral?

Coral bleaching, which often results in the mass mortality of corals and in the collapse of coral reef ecosystems, has become an important issue around the world, with the number of coral reefs decreasing annually. Associate Professor Kazuhiko Koike and Ms. Lisa Fujise of the Graduate School of Biosphere Science at Hiroshima University and their collaborators have proposed mechanisms that might cause coral bleaching and damage. This research group demonstrated that corals more actively digest and expel damaged symbiotic zooxanthellae under conditions of thermal stress, and that this is likely to be a mechanism that helps corals to cope with environmental change. On the other hand, if the stressful conditions… Read more

A novel technique for gene insertion by genome editing

A novel technique for gene insertion by genome editing

Easy, accurate, and highly efficient gene knock-in in a variety of cells and organisms Using a novel gene knock-in technique, effective insertion of an exogenous gene was demonstrated in human cells and in animal models, including silkworms and frogs. This strategy universally enables gene knock-in not only in cultured cells, but also in various organisms. Genome editing using programmable nucleases enables homologous recombination (HR)-mediated gene knock-in. HR activity, however, is relatively low in most cultured cells and organisms. This problem presents technical hurdles for the application of HR-mediated knock-in technology in the field of life sciences. Professor Takashi Yamamoto and his colleagues, Dr. Ken-ichi T. Suzuki and Dr. Tetsushi Sakuma,… Read more