+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

A novel member of the RNase D exoribonuclease family functions in mitochondrial guide RNA metabolism in Trypanosoma brucei

, : A novel member of the RNase D exoribonuclease family functions in mitochondrial guide RNA metabolism in Trypanosoma brucei. Journal of Biological Chemistry 286(12): 10329-10340

RNA turnover and RNA editing are essential for regulation of mitochondrial gene expression in Trypanosoma brucei. RNA turnover is controlled in part by RNA 3' adenylation and uridylation status, with trans-acting factors also impacting RNA homeostasis. However, little is known about the mitochondrial degradation machinery or its regulation in T. brucei. We have identified a mitochondrial exoribonuclease, TbRND, whose expression is highly up-regulated in the insect proliferative stage of the parasite. TbRND shares sequence similarity with RNase D family enzymes but differs from all reported members of this family in possessing a CCHC zinc finger domain. In vitro, TbRND exhibits 3' to 5' exoribonuclease activity, with specificity toward uridine homopolymers, including the 3' oligo(U) tails of guide RNAs (gRNAs) that provide the sequence information for RNA editing. Several lines of evidence generated from RNAi-mediated knockdown and overexpression cell lines indicate that TbRND functions in gRNA metabolism in vivo. First, TbRND depletion results in gRNA tails extended by 2-3 nucleotides on average. Second, overexpression of wild type but not catalytically inactive TbRND results in a substantial decrease in the total gRNA population and a consequent inhibition of RNA editing. The observed effects on the gRNA population are specific as rRNAs, which are also 3'-uridylated, are unaffected by TbRND depletion or overexpression. Finally, we show that gRNA binding proteins co-purify with TbRND. In summary, TbRND is a novel 3' to 5' exoribonuclease that appears to have evolved a function highly specific to the mitochondrion of trypanosomes.


PMID: 21252235

DOI: 10.1074/jbc.M110.152439

Other references

Ewertsen, H.W.; Birk-Nielsen, H., 1973: Social hearing handicap index. Social handicap in relation to hearing impairment. Audiology 12(3): 180-187

van Ruitenbeek, F.; van der Meer, F., 2008: How to determine the geologic controls on the spatial distribution of hydrothermal alteration minerals in hyperspectral imagery. Airborne hyperspectral remote sensing provides detailed mineralogical information of the earth surface at high spatial resolution. In exposed terrains surface mineralogy reflects bed rock mineralogy and can be used to study geologic that were acti...

Lee, S.S.; Yang, B.S.; Yang, Y.H.; Kang, S.Y.; Ko, S.B.; Jung, J.K.; Oh, W.Y.; Oh, S.J.; Kim, K.I., 2002: Analysis of Melanocortin receptor 1 (MC1R) genotype in Korean Brindle Cattle and Korean Cattle with dark muzzle. PCR-RFLP analysis was carried out to investigate the genotype of Melanocortin receptor 1 (MCR1R) gene in Korean Brindle Cattle and Korean Cattle with dark muzzle, which were coat colour and muzzle pigmentation variants of Korean Cattle. Allelic va...

Terry, K., 1993: How much preventive care can we afford?. Medical Economics 70(16): 124-30, 132, 135-6

Baylin, S.B.; Abeloff, M.D.; Wieman, K.C.; Tomford, J.W.; Ettinger, D.S., 1975: Elevated histaminase (diamine oxidase) activity in small-cell carcinoma of the lung. To investigate the possible embryologic relation between small-cell carcinoma of the lung and medullary thyroid carcinoma, we measured plasma histaminase (an enzyme found in medullary carcinoma tissue) in 25 patients with small-cell tumors. The as...

Castro-Vázquez, G., 2016: Late-in-life childbearing (kōrei shussan) in contemporary Japan. This paper draws on interviews with a group of 27 Japanese women who were classified as late-in-life-childbearing mothers, or kōrei shussan--women who had had their first delivery at 35 years of age or over. In making sense of the significance, s...

Fitzwilliam, D.C.L.; Lister, J., 1950: Lord Lister, a new approach. Nursing Times 46(23): 611-611

Bachinski S.W.; Scott R.B., 1976: Rare-earth and other trace element constraints on the origin of mica-lamprophyres. Eos, Transactions, American Geophysical Union 57(12): 1018

Johnson, P.A.; Vaidyanathan, L., 1993: Foliar phosphate applications to potatoes. Journal of the Science of Food & Agriculture 63(1): 124

Kuroda, R.; Kawabata, A.; Kawao, N.; Umeda, W.; Takemura, M.; Shigenaga, Y., 2000: Somatosensory cortex stimulation-evoked analgesia in rats: Potentiation by no synthase inhibition. Clinical and immunohistochemical evidence suggests the possible significance of electrical stimulation of the secondary somatosensory cortex (S-II) as an analgesic therapy. The aim of the present study was to gain behavioral evidence for S-II stim...