Wyniki wyszukiwania

1

Ewolucja genomów mitochondrialnych

100%

Stepien P. P.

Postępy Mikrobiologii

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1983

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tom 22

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nr 1

2

Metabolizm RNA w mitochondriach drozdzy Saccharomyces cerevisiae

84%

Malewicz M., Stepien P. P.

Kosmos

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1997

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tom 46

|

nr 1

65-70

3

Mechanizmy degradacji mRNA

84%

Malecki M., Stepien P. P.

Postępy Biochemii

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2003

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tom 49

|

nr 2

58-67

4

Prediction of the structure of the common perimitochondrial localization signal of nuclear transcripts in yeast

68%

Ejsmont R. K., Golik P., Stepien P. P.

Acta Biochimica Polonica

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2007

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tom 54

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nr 1

Many nuclear genes encoding mitochondrial proteins require specific localization of their mRNAs to the vicinity of mitochondria for proper expression. Studies in Saccharomyces cerevisiae have shown that the cis-acting signal responsible for subcellular localization of mRNAs is localized in the 3' UTR of the transcript. In this paper we present an in silico approach for prediction of a common perimitochondrial localization signal of nuclear transcripts encoding mitochondrial proteins. We computed a consensus structure for this signal by comparison of 3' UTR models for about 3000 yeast transcripts with known localization. Our studies show a short stem-loop structure which appears in most mRNAs localized to the vicinity of mitochondria. The degree of similarity of a given 3' UTR to our consensus structure strongly correlates with experimentally determined perimitochondrial localization of the mRNA, therefore we believe that the structure we predicted acts as a subcellular localization signal. Since our algorithm operates on structures, it seems to be more reliable than sequence-based algorithms. The good predictive value of our model is supported by statistical analysis.

5

A novel restriction endonuclease UnbI, a neoschizomer of Sau96I from an unidentified psychrofilic bacterium from Antarctica is inhibited by phosphate ions

68%

Kawalec M., Borsuk P., Piechula S., Stepien P. P.

Acta Biochimica Polonica

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1997

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tom 44

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nr 4

A novel type II restriction endonuclease UnbI was isolated from an unidentified psychrofilic bacterial strain from Antarctica. UnbI recognizes and cleaves the sequence 5'-GGNCC-3', producing 5 nucleotide long sticky ends. In this respect it differs from its neoschizomer Sau96I and all other restriction enzymes recognizing this sequence. UnbI has a relatively low temperature optimum of 15 degrees C to 20 degrees C and its activity is completely inhibited by inorganic phosphate.

6

Wytwarzanie glukoamylazy przez skonstruowane metodami inzynierii genetycznej transformanty Aspergillus w warunkach hodowli w podlozach cieklych i stalych

51%

Ryszka L., Czakaj J., Sawicka-Zujowska R., Stepien P. P., Weglenski P., Jedrychowska B., Hoffman-Zacharska D.

Prace Instytutów i Laboratoriów Badawczych Przemysłu Spożywczego

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2002

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tom 57

7-26

7

Human SUV3 helicase in the cell nucleus regulates the growth rate of HeLa cells

51%

Szewczyk M., Fedoryszak-Kuska N., Tkaczuk K., Dobrucki J., Waligorska A., Stepien P. P.

Acta Biochimica Polonica

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2017

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tom 64

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nr 1

8

Yeast nuclear PET127 gene can suppress deletions of the SUV3 or DSS1 genes: An indication of a functional interaction between 3' and 5' ends of mitochondrial mRNAs

51%

Wegierski T., Dmochowska A., Jablonowska A., Dziembowski A., Bartnik E., Stepien P. P.

Acta Biochimica Polonica

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1998

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tom 45

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nr 4

Saccharomyces cerevisiae nuclear genes SUV3 and DSS1 encode putative RNA helicase and RNase II, respectively, which are subunits of the mitochondrial degradosome (mtEXO): a three-protein complex which has a 3' to 5' exoribonuclease activity and plays a major role in regulating stability of mitochondrial RNA. Lack of either of the two gene products results in a respiratory negative phenotype, while on the molecular level it causes a total block of mitochondrial translation, loss of the in vitro exoribonuclease activity and changes in stability and processing of many mtRNAs. We have found that the yeast nuclear gene PET127 present on a low or high copy number vector can effectively suppress the effects of the SUV3 or DSS1 gene disruptions. Since the product of the PET127 gene is involved in processing of the 5' ends of mitochondrial mRNAs, we suggest that there is a functional coupling between the 5' and 3' ends of mitochondrial mRNAs.

9

Evolutionary conservation of the transcribed spacer sequences of the rDNA repeat unit in three species of the genus Aspergillus

51%

Borsuk P., Gniadkowski M., Kucharski R., Bisko M., Kanabus M., Stepien P. P., Bartnik E.

Acta Biochimica Polonica

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1994

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tom 41

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nr 1

We have cloned and sequenced the two intervening transcribed spacers in the rDNA repeat unit of three Aspergillus species — A. nidulans, A. aw amort and A. wentii. The A. wentii and A. awamori spacers are almost identical and share a high degree of homology with the A. nidulans spacers. All spacers have a high G-C content (66%-76%) and the potential of forming complex secondary structures, which may indicate that they play a role in the maturation of pre-rRNA molecules.

10

Up-regulation of human PNPase mRNA by beta-interferon has no effect on protein level in melanoma cell lines

43%

Gewartowski K., Tomecki R., Muchowski L., Dmochowska A., Dzwonek A., Malecki M., Skurzak H., Ostrowski J., Stepien P. P.

Acta Biochimica Polonica

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2006

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tom 53

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nr 1

Human mitochondrial polynucleotide phosphorylase (hPNPase) is an exoribonuclease localized in mitochondria. The exact physiological function of this enzyme is unknown. Recent studies have revealed the existence of a relationship between induction of hPNPase mRNA and both cellular senescence and growth arrest of melanoma cells following β-interferon treatment. The aim of this study was to verify whether the augmented hPNPase mRNA level results in increase of the protein level. In several cell lines established from five metastatic melanoma patients we did not find any such correlation. However, an elevated level of hPNPase protein was observed in interferon-induced HeLa and Jurkat cells. This increase was correlated with a slight shortening of poly(A) tails of mitochondrial ND3 transcript.

11

Differential stability of mitochondrial mRNA in HeLa cells

43%

Piechota J., Tomecki R., Gewartowski K., Szczesny R., Dmochowska A., Kudla M., Dybczynska L., Stepien P. P., Bartnik E.

Acta Biochimica Polonica

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2006

|

tom 53

|

nr 1

The physiological significance and metabolism of oligoadenylated and polyadenylated human mitochondrial mRNAs are not known to date. After study of eight mitochondrial transcripts (ND1, ND2, ND3, ND5, CO1, CO2, ATP6/8 and Cyt. b) we found a direct correlation between the half-lives of mitochondrial mRNAs and their steady-state levels. Investigation of the mt-mRNA decay after thiamphenicol treatment indicated that three transcripts (ND2, ND3 and Cyt. b) are significantly stabilized after inhibition of mitochondrial translation. Careful analysis one of them, ND3, showed that inaccurate processing of the H-strand RNA precursor may occasionally occur between the ND3 and tRNAArg locus leading to synthesis of ND3 mRNAs lacking the STOP codon. However, analysis of the oligo(A) fraction observed in case of the ND3 indicates that partially polyadenylated mRNAs are linked rather to the transcription process than to the translation-dependent deadenylation. Analysis of ND3 mRNA turnover in cells with siRNA-mediated knock-down of the mitochondrial poly(A) polymerase shows that strongly decreased polyadenylation does not markedly affect the decay of this transcript. We present a model where oligoadenylated mitochondrial transcripts are precursors of molecules containing full length poly(A) tails.

Ograniczanie wyników

Ewolucja genomów mitochondrialnych

Metabolizm RNA w mitochondriach drozdzy Saccharomyces cerevisiae

Mechanizmy degradacji mRNA

Prediction of the structure of the common perimitochondrial localization signal of nuclear transcripts in yeast

A novel restriction endonuclease UnbI, a neoschizomer of Sau96I from an unidentified psychrofilic bacterium from Antarctica is inhibited by phosphate ions

Wytwarzanie glukoamylazy przez skonstruowane metodami inzynierii genetycznej transformanty Aspergillus w warunkach hodowli w podlozach cieklych i stalych

Human SUV3 helicase in the cell nucleus regulates the growth rate of HeLa cells

Yeast nuclear PET127 gene can suppress deletions of the SUV3 or DSS1 genes: An indication of a functional interaction between 3' and 5' ends of mitochondrial mRNAs

Evolutionary conservation of the transcribed spacer sequences of the rDNA repeat unit in three species of the genus Aspergillus

Up-regulation of human PNPase mRNA by beta-interferon has no effect on protein level in melanoma cell lines

Differential stability of mitochondrial mRNA in HeLa cells