Unknown,Transcriptomics,Genomics,Proteomics

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Nuclear pore complex evolution: A trypanosome Mlp analog functions in chromosomal segregation but lacks transcriptional barrier activity

ABSTRACT: The nuclear pore complex (NPC) has dual roles in nucleocytoplasmic transport and chromatin organisation. In many eukaryotes the coiled coil Mlp/Tpr proteins of the NPC nuclear basket have specific roles in interactions with chromatin and defining specialised regions of active transcription, while Mlp2 associates with the mitotic spindle in a cell-cycle dependent manner. We previously identified two putative Mlp-related proteins in African trypanosomes, TbNup110 and TbNup92, the latter of which associates with the spindle. We now provide evidence for independent ancestry for TbNup92/TbNup110 and Mlp/Tpr proteins. However, TbNup92 is required for correct chromosome segregation, with knockout cells exhibiting microaneuploidy and low fidelity telomere segregation. Further, TbNup92 is intimately associated with the mitotic spindle and spindle anchor site, but apparently has minimal roles in the control of gene transcription, indicating that TbNup92 lacks major barrier activity. TbNup92 therefore acts as a functional analog of Mlp/Tpr proteins, and together with the lamina analog NUP-1, represents a cohort of novel proteins operating at the nuclear periphery of trypanosomes, uncovering complex evolutionary trajectories for the NPC and nuclear lamina. Whole transcriptome comparison between parental and TbNup92? cells

ORGANISM(S): Trypanosoma brucei

SUBMITTER: Alexander Ratushny

PROVIDER: E-GEOD-56436 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Nuclear pore complex evolution: A trypanosome Mlp analog functions in chromosomal segregation but lacks transcriptional barrier activity

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