Biologists Discover Motor Protein That Rewinds DNA

piggy submitted, created time 1 month 9 hours (www.sciencedaily.com)

ScienceDaily (Nov. 2, 2008) — Two biologists at the University of California, San Diego have discovered the first of a new class of cellular motor proteins that “rewind” sections of the double-stranded DNA molecule that become unwound, like the tangled ribbons from a cassette tape, in “bubbles” that prevent critical genes from being expressed.

“When your DNA gets stuck in the unwound position, your cells are in big trouble, and in humans, that ultimately leads to death” said Jim Kadonaga, a professor of biology at UCSD who headed the study

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The mechanics of translocation

jerry submitted, created time 5 months 4 weeks (www.sciencedirect.com)

Stepwise addition of amino acids to the growing polypeptide chain requires the coordinated movement of mRNA and tRNAs through the ribosome, a process known as translocation. Researchers review current understanding of the kinetics and mechanics of translocation, with emphasis on the structure of a functional mammalian ribosome stalled during translocation by an mRNA pseudoknot.

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Genome wide transcriptional analysis of resting and IL2 activated human natural killer cells: gene expression signatures indicative of novel molecular signaling pathways

captainclaw submitted, created time 1 year 4 months (www.biomedcentral.com)

"This analysis allowed us to identify genes implicated in cellular quiescence and the cytokines and cytotoxic factors ready for immediate immune response. It also allowed us to observe the sequential immunostimulatory effects of IL2 on NK cells improving our understanding of the biology and molecular mediators behind NK cell activation."

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Sickle cell disease: old discoveries, new concepts, and future promise

medal submitted, created time 1 year 7 months (www.jci.org)

"The discovery of the molecular basis of sickle cell disease was an important landmark in molecular medicine. The modern tools of molecular and cellular biology have refined our understanding of its pathophysiology and facilitated the development of new therapies. In this review, we discuss some of the important advances in this field and the impediments that limit the impact of these advances. "

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Molecular imaging with targeted contrast ultrasound

medal submitted, created time 1 year 8 months (www.sciencedirect.com)

"Molecular imaging with contrast ultrasound relies on the detection of targeted microbubbles or other acoustically active nanoparticles. These microbubbles are retained in diseased tissue where they produce an acoustic signal because of their resonant properties in the ultrasound field. Targeting is accomplished either through manipulating the chemical properties of the microbubble shell or through conjugation of disease-specific ligands for the targeted molecule to the microbubble surface."

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What would be happen for losing of -tubulin polyglutamylation in ROSA22 mice ?

angelfish submitted, created time 1 year 8 months (www.pnas.org)

“Microtubules function as molecular tracks along which motor proteins transport a variety of cargo to discrete destinations within the cell. The carboxyl termini of - and -tubulin can undergo different posttranslational modifications, including polyglutamylation, which is particularly abundant within the mammalian nervous system. Thus, this modification could serve as a molecular "traffic sign" for motor proteins in neuronal cells

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Cyclin D1 expression in mesenchymal cells

crackpot submitted, created time 1 year 9 months (www.jcb.org)

"High molecular weight (HMW) hyaluronan (HA) is widely distributed in the extracellular matrix, but its biological activities remain incompletely understood. We previously reported that HMW-HA binding to CD44 antagonizes mitogen-induced S-phase entry in vascular smooth muscle cells (SMCs; Cuff, C.A., D. Kothapalli, I. Azonobi, S. Chun, Y. Zhang, R. Belkin, C. Yeh, A. Secreto, R.K. Assoian, D.J. Rader, and E. Puré. 2001. J. Clin. Invest. 108:1031–1040); we now characterize the underlying molecular mechanism and document its relevance in vivo

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Found in Brain-obesity Puzzle

angelfish submitted, created time 1 year 10 months (www.sciencedaily.com)

Obesity, whether in mice or humans, is the product of an altered balance between energy intake and energy use. Using a variety of genetic, diet and hormone techniques, U-M researchers were able to show that the action of SH2B1 regulates body weight, a single protein in brain cells may act as a linchpin in the body's weight-regulating system, playing a key role in the flurry of signals that govern fat storage, sugar use, energy balance and weight.

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