Scientists 'Watch' Formation of Cells' Protein Factories, Ribosomes, for First Time
ScienceDaily (Nov. 1, 2010) — A team from The Scripps Research Institute has revealed the first-ever pictures of the formation of cells' "protein factories." In addition to being a major technical feat on its own, the work could open new pathways for development of antibiotics and treatments for diseases tied to errors in ribosome formation. In addition, the techniques developed in the study can now be applied to other complex challenges in the understanding of cellular processes. [*]
A team from The Scripps Research Institute has revealed the first-ever pictures of the formation of cells’ “protein factories.” (Credit: Gabe Lander)
Identifying and observing the molecules that form ribosomes -- the cellular factories that build the proteins essential for life -- has for decades been a key goal for biologists but one that had seemed nearly unattainable. But the new Scripps Research study, which appears in the October 29, 2010 issue of the journal Science, yielded pictures of the chemical intermediate steps in ribosome creation.
"For me it was a dream experiment," said project leader James Williamson, Ph.D., professor, member of the Skaggs Institute for Chemical Biology, and dean of graduate and postgraduate studies at Scripps Research, who credits collaborators at the Scripps Research National Resource for Automated Molecular Microscopy (NRAMM) facility for making it possible. "We have great colleagues at Scripps to collaborate with who are willing to try some crazy experiments, and when they work it's just beautiful."
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Read more here/Leia mais aqui: Science Daily
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Science 29 October 2010:
Vol. 330. no. 6004, pp. 673 - 677
DOI: 10.1126/science.1193220
Visualizing Ribosome Biogenesis: Parallel Assembly Pathways for the 30S Subunit
Anke M. Mulder,1 Craig Yoshioka,1 Andrea H. Beck,2 Anne E. Bunner,2 Ronald A. Milligan,1Clinton S. Potter,1 Bridget Carragher,1 James R. Williamson2,*
Ribosomes are self-assembling macromolecular machines that translate DNA into proteins, and an understanding of ribosome biogenesis is central to cellular physiology. Previous studies on the Escherichia coli 30S subunit suggest that ribosome assembly occurs via multiple parallel pathways rather than through a single rate-limiting step, but little mechanistic information is known about this process. Discovery single-particle profiling (DSP), an application of time-resolved electron microscopy, was used to obtain more than 1 million snapshots of assembling 30S subunits, identify and visualize the structures of 14 assembly intermediates, and monitor the population flux of these intermediates over time. DSP results were integrated with mass spectrometry data to construct the first ribosome-assembly mechanism that incorporates bindingdependencies, rate constants, and structural characterization of populated intermediates.
1 Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
2 Departments of Molecular Biology and Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
* To whom correspondence should be addressed. E-mail: jrwill@scripps.edu
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NOTA DESTE BLOGGER:
A cada pesquisa que leio fico impressionado que, a cada nível atingido, mais e mais complexidade nas formas bióticas são descobertas com o agravante heurístico que o paradigma darwiniano NÃO EXPLICA ESSA COMPLEXIDADE.
Aprendi na universidade que quando uma teoria científica não responde ou não explica certos fenômenos, ela deve ser ser revista ou simplesmente descartada. Srs., o que está faltando para descartar Darwin na lata do lixo histórico? Mais ciência e menos ideologia???
Fui, nem sei por que, pensando que muito do que é feito em ciência atualmente é alquimia pura, com o aval da Nomenklatura científica, que com mão de ferro a la Stalin, defende dogmas indefensáveis no contexto de justificação teórica.
Pobre ciência... sniff, sniff, sniff...
