Characterization and differential nuclear localization of Nopp140 and a novel Nopp140-like protein in trypanosomes.
نویسندگان
چکیده
Trypanosomatids possess two homologues of Nopp140: a canonical Nopp140 and a Nopp140-like protein (TbNoLP) in which a GAR domain replaces the C-terminal SRP40 domain. Both are phosphorylated and coimmunoprecipitate with RNA polymerase I. Each paralogue has a distinct subnuclear localization, and depletion of TbNoLP produces an enlarged nucleolus in which TbNopp140-containing regions disperse. The restricted occurrence pattern of NoLP proteins reflects an intriguing convergence in evolution, suggestive of a function in nucleoplasmic small nucleolar ribonucleoprotein shuttling.
منابع مشابه
NAP57, a mammalian nucleolar protein with a putative homolog in yeast and bacteria [published erratum appears in J Cell Biol 1998 Jan 26;140(2):447]
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ورودعنوان ژورنال:
- Eukaryotic cell
دوره 5 5 شماره
صفحات -
تاریخ انتشار 2006