کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2181245 1095283 2009 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
An unusual organelle in Cryptococcus neoformans links luminal pH and capsule biosynthesis
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیولوژی سلول
پیش نمایش صفحه اول مقاله
An unusual organelle in Cryptococcus neoformans links luminal pH and capsule biosynthesis
چکیده انگلیسی

Cryptococcus neoformans is a basidiomycete that causes deadly infections in the immunocompromised. We previously generated a secretion mutant in this fungus by introducing a mutation in the SAV1 gene, which encodes a homolog of the Sec4/Rab8 subfamily GTPases. Under restrictive conditions there are two notable morphological changes in the sav1 mutant: accumulation of post-Golgi vesicles and the appearance of an unusual organelle, which we term the sav1 body (SB). The SB is an electron-transparent structure 0.2–1 μm in diameter, with vesicles or other membranous structures associated with the perimeter. Surprisingly, the SB was heavily labeled with anti-glucuronoxylomannan (GXM) antibodies, suggesting that it contains a secreted capsule component, GXM. A structure similar to the SB, also labeled by anti-GXM antibodies, was induced in wild type cells treated with the vacuolar-ATPase inhibitor, bafilomycin A1. Bafilomycin A1 and other agents that increase intraluminal pH also inhibited capsule polysaccharide shedding and capsule growth. These studies highlight an unusual organelle observed in C. neoformans with a potential role in polysaccharide synthesis, and a link between luminal pH and GXM biosynthesis.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Fungal Genetics and Biology - Volume 46, Issue 9, September 2009, Pages 682–687
نویسندگان
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