Complexidade da divisão celular: mero acaso, fortuita necessidade ou design inteligente?

sexta-feira, setembro 03, 2010

The Protein Composition of Mitotic Chromosomes Determined Using Multiclassifier Combinatorial Proteomics

Cell, Volume 142, Issue 5, 810-821, 3 September 2010
Copyright © 2010 Elsevier Inc. All rights reserved.
10.1016/j.cell.2010.07.047

Authors

Shinya Ohta,Jimi-Carlo Bukowski-Wills,Luis Sanchez-Pulido,Flavia de Lima Alves,Laura Wood,Zhuo A. Chen,Melpi Platani,Lutz Fischer,Damien F. Hudson,Chris P. Ponting,Tatsuo Fukagawa,William C. Earnshaw,Juri Rappsilber See Affiliations



Highlights

Method to define the protein composition of a complex nonpurifiable organelle
Combines genetics and proteomics to study complexes in whole chromosomes
Use of machine learning to uncover functional relationships between proteins
Comprehensive list of >4000 mitotic chromosome-associated proteins

Summary

Despite many decades of study, mitotic chromosome structure and composition remain poorly characterized. Here, we have integrated quantitative proteomics with bioinformatic analysis to generate a series of independent classifiers that describe the ∼4,000 proteins identified in isolated mitotic chromosomes. Integrating these classifiers by machine learning uncovers functional relationships between protein complexes in the context of intact chromosomes and reveals which of the ∼560 uncharacterized proteins identified here merits further study. Indeed, of 34 GFP-tagged predicted chromosomal proteins, 30 were chromosomal, including 13 with centromere-association. Of 16 GFP-tagged predicted nonchromosomal proteins, 14 were confirmed to be nonchromosomal. An unbiased analysis of the whole chromosome proteome from genetic knockouts of kinetochore protein Ska3/Rama1 revealed that the APC/C and RanBP2/RanGAP1 complexes depend on the Ska complex for stable association with chromosomes. Our integrated analysis predicts that up to 97 new centromere-associated proteins remain to be discovered in our data set.

+++++

Professores, pesquisadores e alunos de universidades públicas e privadas com acesso ao site CAPES/Periódicos podem ler gratuitamente este artigo da Cell e de mais 22.440 publicações científicas.


+++++


NOTA IMPERTINENTE DESTE BLOGGER:


4.000 proteínas envolvidas na divisão celular, e todas elas evoluíram aleatoriamente para funcionarem harmoniosamente??? Para pensar cum grano salis: sendo assim a evolução pode nos dizer quantos anjos dançam na cabeça de um alfinete...


Fui, nem sei porque, pensando e cada vez menos convencido do poder criativo da seleção natural ou n mecanismos evolucionários [de A a Z] para explicar a complexidade e diversidade das formas bióticas. Ou será que eu não tenho fé suficiente para acreditar em Darwin, o homem que teve a maior ideia que toda a humanidade já teve???

+++++