tailieunhanh - Báo cáo sinh học: "Adaptive evolution of centromere proteins in plants and animals"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Adaptive evolution of centromere proteins in plants and animals. | J. Biol. Journal of Biology BioMed Central Research article Open Access Adaptive evolution of centromere proteins in plants and animals Paul B Talbert Terri D Bryson and Steven Henikoff Address Howard Hughes Medical Institute Fred Hutchinson Cancer Research Center 1100 Fairview Avenue N Seattle WA 98109-1024 USA. Correspondence Steven Henikoff. E-mail steveh@ Published 31 August 2004 Received 25 May 2004 Revised 20 July 2004 Journal of Biology 2004 3 18 Accepted 22 July 2004 The electronic version of this article is the complete one and can be found online at http content 3 4 18 2004 Talbert et al. licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background Centromeres represent the last frontiers of plant and animal genomics. Although they perform a conserved function in chromosome segregation centromeres are typically composed of repetitive satellite sequences that are rapidly evolving. The nucleosomes of centromeres are characterized by a special H3-like histone CenH3 which evolves rapidly and adaptively in Drosophila and Arabidopsis. Most plant animal and fungal centromeres also bind a large protein centromere protein C CENP-C that is characterized by a single 24 amino-acid motif CENPC motif . Results Whereas we find no evidence that mammalian CenH3 CENP-A has been evolving adaptively mammalian CENP-C proteins contain adaptively evolving regions that overlap with regions of DNA-binding activity. In plants we find that CENP-C proteins have complex duplicated regions with conserved amino and carboxyl termini that are dissimilar in sequence to their counterparts in animals and fungi. Comparisons of Cenpc genes from Arabidopsis species and from grasses revealed multiple regions that are under .