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Mitochondrial ribosome

January 01, 1970

The mitochondrial ribosome, or mitoribosome, is a protein complex that is active in mitochondria and functions as a riboprotein for translating mitochondrial mRNAs encoded in mtDNA. The mitoribosome is attached to the inner mitochondrial membrane.[1] Mitoribosomes, like cytoplasmic ribosomes, consist of two subunits — large (mt-LSU) and small (mt-SSU).[2] Mitoribosomes consist of several specific proteins and fewer rRNAs.[2] While mitochondrial rRNAs are encoded in the mitochondrial genome, the proteins that make up mitoribosomes are encoded in the nucleus and assembled by cytoplasmic ribosomes before being implanted into the mitochondria.[3]

A diagram showing mtDNA (circular) and mitochondrial ribosomes among other mitochondria structures

Function edit

Mitochondria contain around 1000 proteins in yeast and 1500 proteins in humans. However, only 8 and 13 proteins are encoded in mitochondrial DNA in yeast and humans respectively. Most mitochondrial proteins are synthesized via cytoplasmic ribosomes.[4] Proteins that are key components in the electron transport chain are translated in mitochondria.[5][6]

Structure edit

Mammalian mitoribosomes have small 28S and large 39S subunits, together forming a 55S mitoribosome.[7][8] Plant mitoribosomes have small 33S and large 50S subunits, together forming a 78S mitoribosome.[7][8]

Animal mitoribosomes only have two rRNAs, 12S (SSU) and 16S (LSU), both highly minimized compared to their larger homologues.[7] Most eukaryotoes use 5S mitoribosomal RNA, animals, fungi, alveolates and euglenozoans being the exceptions.[9] A variety of methods have evolved to fill in the gap left by a missing 5S, with animals co-opting a Mt-tRNA (Val in vertebrates).[7][10]

Comparison to other ribosomes edit

Like mitochondria itself is descended from bacteria, mitochondrial ribosomes are descended from bacterial ribosomes.[1] As mitochondria evolved however, the mitoribosome has significantly diverged from its bacterial cousins leading to differences in configuration and function.[1] In configuration, the mitoribosome includes additional proteins in both its large and small subunits.[1] In function, mitoribosomes are much more limited in the proteins they translate, only producing a few proteins, used mostly in the mitochondrial membrane. [1] Below is a table showing some properties of different ribosomes:

Properties of mitoribosomes
Bacteria[1][11] Cytosolic (Eukaryote)[11][1] Mammalian mitochondria[1][11] Yeast Mitochondria[1][11] Plant Mitochondria [12]
Sedimentation Coefficient (LSU/SSU) 70S (50S/30S) 80S (60S/40S) 55S (39S/28S) 74S (54S/37S) ~80S
Number of proteins (LSU/SSU) 54 (33/21) 79-80 (46-47/33) 80 (50/30) 84 (46/38) 68-80
Number of rRNAs (LSU/SSU) 3 (2/1) 4 (3/1) 3 (2/1) 2 (1/1) 3 (2/1)

Diseases edit

As the mitoribosome is responsible for the manufacture of proteins necessary for the electron transport chain, malfunctions in the mitoribosome can result in metabolic disease.[13] [3] In humans, disease particularly manifests in energy-reliant organs such as the heart, brain, and muscle.[3] Disease either originates from mutations in mitochondrial rRNA or genes encoding the mitoribosomal proteins.[3] In the case of mitoribosomal protein mutation, heredity of disease follows Mendelian inheritance as these proteins are encoded in the nucleus.[13] On the other hand, because mitochondrial rRNA is encoded in the mitochondria, mutations in rRNA are maternally inherited.[13] Examples of diseases in humans caused by these mutations include Leigh syndrome, deafness, neurological disorders, and various cardiomyopathies.[13] In plants, mutation in mitoribosomal proteins can result in stunted size and distorted leaf growth.[14]

Genes edit

The mitochondrial ribosomal protein nomenclature generally follows that of bacteria, with extra numbers used for mitochondrion-specific proteins. (For more information on the nomenclature, see Ribosomal protein § Table of ribosomal proteins.)

References edit

  1. ^ a b c d e f g h i Greber BJ, Ban N (June 2016). "Structure and Function of the Mitochondrial Ribosome". Annual Review of Biochemistry. 85 (1): 103–132. doi:10.1146/annurev-biochem-060815-014343. PMID 27023846.
  2. ^ a b Amunts A, Brown A, Toots J, Scheres SH, Ramakrishnan V (April 2015). "Ribosome. The structure of the human mitochondrial ribosome". Science. 348 (6230): 95–98. doi:10.1126/science.aaa1193. PMC 4501431. PMID 25838379.
  3. ^ a b c d Sylvester JE, Fischel-Ghodsian N, Mougey EB, O'Brien TW (March 2003). "Mitochondrial ribosomal proteins: candidate genes for mitochondrial disease". Genetics in Medicine. 6 (2): 73–80. doi:10.1097/01.GIM.0000117333.21213.17. PMID 15017329. S2CID 22169585.
  4. ^ Wenz LS, Opaliński Ł, Wiedemann N, Becker T (May 2015). "Cooperation of protein machineries in mitochondrial protein sorting". Biochimica et Biophysica Acta (BBA) - Molecular Cell Research. 1853 (5): 1119–1129. doi:10.1016/j.bbamcr.2015.01.012. PMID 25633533.
  5. ^ Johnston IG, Williams BP (February 2016). "Evolutionary Inference across Eukaryotes Identifies Specific Pressures Favoring Mitochondrial Gene Retention". Cell Systems. 2 (2): 101–111. doi:10.1016/j.cels.2016.01.013. PMID 27135164.
  6. ^ Hamers L (2016). "Why do our cell's power plants have their own DNA?". Science. doi:10.1126/science.aaf4083.
  7. ^ a b c d Greber BJ, Bieri P, Leibundgut M, Leitner A, Aebersold R, Boehringer D, Ban N (April 2015). "Ribosome. The complete structure of the 55S mammalian mitochondrial ribosome". Science. 348 (6232): 303–308. doi:10.1126/science.aaa3872. hdl:20.500.11850/100390. PMID 25837512. S2CID 206634178.
  8. ^ a b Spremulli LL (2016-01-01). "The Protein Biosynthetic Machinery of Mitochondria". In Bradshaw RA, Stahl PD (eds.). Encyclopedia of Cell Biology. Waltham: Academic Press. pp. 545–554. doi:10.1016/b978-0-12-394447-4.10066-5. ISBN 978-0-12-394796-3.
  9. ^ Valach M, Burger G, Gray MW, Lang BF (December 2014). "Widespread occurrence of organelle genome-encoded 5S rRNAs including permuted molecules". Nucleic Acids Research. 42 (22): 13764–13777. doi:10.1093/nar/gku1266. PMC 4267664. PMID 25429974.
  10. ^ Brown A, Amunts A, Bai XC, Sugimoto Y, Edwards PC, Murshudov G, et al. (November 2014). "Structure of the large ribosomal subunit from human mitochondria". Science. 346 (6210): 718–722. Bibcode:2014Sci...346..718B. doi:10.1126/science.1258026. PMC 4246062. PMID 25278503.
  11. ^ a b c d De Silva D, Tu YT, Amunts A, Fontanesi F, Barrientos A (2015-07-18). "Mitochondrial ribosome assembly in health and disease". Cell Cycle. 14 (14): 2226–2250. doi:10.1080/15384101.2015.1053672. PMC 4615001. PMID 26030272.
  12. ^ Robles P, Quesada V (December 2017). "Emerging Roles of Mitochondrial Ribosomal Proteins in Plant Development". International Journal of Molecular Sciences. 18 (12): 2595. doi:10.3390/ijms18122595. PMC 5751198. PMID 29207474.
  13. ^ a b c d De Silva D, Tu YT, Amunts A, Fontanesi F, Barrientos A (2015-07-18). "Mitochondrial ribosome assembly in health and disease". Cell Cycle. 14 (14): 2226–2250. doi:10.1080/15384101.2015.1053672. PMC 4615001. PMID 26030272.
  14. ^ Robles P, Quesada V (December 2017). "Emerging Roles of Mitochondrial Ribosomal Proteins in Plant Development". International Journal of Molecular Sciences. 18 (12): 2595. doi:10.3390/ijms18122595. PMC 5751198. PMID 29207474.

Further reading edit

  • Greber BJ, Ban N (June 2016). "Structure and Function of the Mitochondrial Ribosome". Annual Review of Biochemistry. 85: 103–132. doi:10.1146/annurev-biochem-060815-014343. PMID 27023846.
 

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January 01, 1970
mitochondrial, ribosome, mitochondrial, ribosome, mitoribosome, protein, complex, that, active, mitochondria, functions, riboprotein, translating, mitochondrial, mrnas, encoded, mtdna, mitoribosome, attached, inner, mitochondrial, membrane, mitoribosomes, like. The mitochondrial ribosome or mitoribosome is a protein complex that is active in mitochondria and functions as a riboprotein for translating mitochondrial mRNAs encoded in mtDNA The mitoribosome is attached to the inner mitochondrial membrane 1 Mitoribosomes like cytoplasmic ribosomes consist of two subunits large mt LSU and small mt SSU 2 Mitoribosomes consist of several specific proteins and fewer rRNAs 2 While mitochondrial rRNAs are encoded in the mitochondrial genome the proteins that make up mitoribosomes are encoded in the nucleus and assembled by cytoplasmic ribosomes before being implanted into the mitochondria 3 A diagram showing mtDNA circular and mitochondrial ribosomes among other mitochondria structures Contents 1 Function 2 Structure 3 Comparison to other ribosomes 4 Diseases 5 Genes 6 References 7 Further readingFunction editMitochondria contain around 1000 proteins in yeast and 1500 proteins in humans However only 8 and 13 proteins are encoded in mitochondrial DNA in yeast and humans respectively Most mitochondrial proteins are synthesized via cytoplasmic ribosomes 4 Proteins that are key components in the electron transport chain are translated in mitochondria 5 6 Structure editMammalian mitoribosomes have small 28S and large 39S subunits together forming a 55S mitoribosome 7 8 Plant mitoribosomes have small 33S and large 50S subunits together forming a 78S mitoribosome 7 8 Animal mitoribosomes only have two rRNAs 12S SSU and 16S LSU both highly minimized compared to their larger homologues 7 Most eukaryotoes use 5S mitoribosomal RNA animals fungi alveolates and euglenozoans being the exceptions 9 A variety of methods have evolved to fill in the gap left by a missing 5S with animals co opting a Mt tRNA Val in vertebrates 7 10 Comparison to other ribosomes editLike mitochondria itself is descended from bacteria mitochondrial ribosomes are descended from bacterial ribosomes 1 As mitochondria evolved however the mitoribosome has significantly diverged from its bacterial cousins leading to differences in configuration and function 1 In configuration the mitoribosome includes additional proteins in both its large and small subunits 1 In function mitoribosomes are much more limited in the proteins they translate only producing a few proteins used mostly in the mitochondrial membrane 1 Below is a table showing some properties of different ribosomes Properties of mitoribosomes Bacteria 1 11 Cytosolic Eukaryote 11 1 Mammalian mitochondria 1 11 Yeast Mitochondria 1 11 Plant Mitochondria 12 Sedimentation Coefficient LSU SSU 70S 50S 30S 80S 60S 40S 55S 39S 28S 74S 54S 37S 80S Number of proteins LSU SSU 54 33 21 79 80 46 47 33 80 50 30 84 46 38 68 80 Number of rRNAs LSU SSU 3 2 1 4 3 1 3 2 1 2 1 1 3 2 1 Diseases editAs the mitoribosome is responsible for the manufacture of proteins necessary for the electron transport chain malfunctions in the mitoribosome can result in metabolic disease 13 3 In humans disease particularly manifests in energy reliant organs such as the heart brain and muscle 3 Disease either originates from mutations in mitochondrial rRNA or genes encoding the mitoribosomal proteins 3 In the case of mitoribosomal protein mutation heredity of disease follows Mendelian inheritance as these proteins are encoded in the nucleus 13 On the other hand because mitochondrial rRNA is encoded in the mitochondria mutations in rRNA are maternally inherited 13 Examples of diseases in humans caused by these mutations include Leigh syndrome deafness neurological disorders and various cardiomyopathies 13 In plants mutation in mitoribosomal proteins can result in stunted size and distorted leaf growth 14 Genes editThe mitochondrial ribosomal protein nomenclature generally follows that of bacteria with extra numbers used for mitochondrion specific proteins For more information on the nomenclature see Ribosomal protein Table of ribosomal proteins MRPS1 MRPS2 MRPS3 MRPS4 MRPS5 MRPS6 MRPS7 MRPS8 MRPS9 MRPS10 MRPS11 MRPS12 MRPS13 MRPS14 MRPS15 MRPS16 MRPS17 MRPS18 MRPS19 MRPS20 MRPS21 MRPS22 MRPS23 MRPS24 MRPS25 MRPS26 MRPS27 MRPS28 MRPS29 MRPS30 MRPS31 MRPS32 MRPS33 MRPS34 MRPS35 MRPL1 MRPL2 MRPL3 MRPL4 MRPL5 MRPL6 MRPL7 MRPL8 MRPL9 MRPL10 MRPL11 MRPL12 MRPL13 MRPL14 MRPL15 MRPL16 MRPL17 MRPL18 MRPL19 MRPL20 MRPL21 MRPL22 MRPL23 MRPL24 MRPL25 MRPL26 MRPL27 MRPL28 MRPL29 MRPL30 MRPL31 MRPL32 MRPL33 MRPL34 MRPL35 MRPL36 MRPL37 MRPL38 MRPL39 MRPL40 MRPL41 MRPL42 rRNA MT RNR1 MT RNR2 MT TV mitochondrial References edit a b c d e f g h i Greber BJ Ban N June 2016 Structure and Function of the Mitochondrial Ribosome Annual Review of Biochemistry 85 1 103 132 doi 10 1146 annurev biochem 060815 014343 PMID 27023846 a b Amunts A Brown A Toots J Scheres SH Ramakrishnan V April 2015 Ribosome The structure of the human mitochondrial ribosome Science 348 6230 95 98 doi 10 1126 science aaa1193 PMC 4501431 PMID 25838379 a b c d Sylvester JE Fischel Ghodsian N Mougey EB O Brien TW March 2003 Mitochondrial ribosomal proteins candidate genes for mitochondrial disease Genetics in Medicine 6 2 73 80 doi 10 1097 01 GIM 0000117333 21213 17 PMID 15017329 S2CID 22169585 Wenz LS Opalinski L Wiedemann N Becker T May 2015 Cooperation of protein machineries in mitochondrial protein sorting Biochimica et Biophysica Acta BBA Molecular Cell Research 1853 5 1119 1129 doi 10 1016 j bbamcr 2015 01 012 PMID 25633533 Johnston IG Williams BP February 2016 Evolutionary Inference across Eukaryotes Identifies Specific Pressures Favoring Mitochondrial Gene Retention Cell Systems 2 2 101 111 doi 10 1016 j cels 2016 01 013 PMID 27135164 Hamers L 2016 Why do our cell s power plants have their own DNA Science doi 10 1126 science aaf4083 a b c d Greber BJ Bieri P Leibundgut M Leitner A Aebersold R Boehringer D Ban N April 2015 Ribosome The complete structure of the 55S mammalian mitochondrial ribosome Science 348 6232 303 308 doi 10 1126 science aaa3872 hdl 20 500 11850 100390 PMID 25837512 S2CID 206634178 a b Spremulli LL 2016 01 01 The Protein Biosynthetic Machinery of Mitochondria In Bradshaw RA Stahl PD eds Encyclopedia of Cell Biology Waltham Academic Press pp 545 554 doi 10 1016 b978 0 12 394447 4 10066 5 ISBN 978 0 12 394796 3 Valach M Burger G Gray MW Lang BF December 2014 Widespread occurrence of organelle genome encoded 5S rRNAs including permuted molecules Nucleic Acids Research 42 22 13764 13777 doi 10 1093 nar gku1266 PMC 4267664 PMID 25429974 Brown A Amunts A Bai XC Sugimoto Y Edwards PC Murshudov G et al November 2014 Structure of the large ribosomal subunit from human mitochondria Science 346 6210 718 722 Bibcode 2014Sci 346 718B doi 10 1126 science 1258026 PMC 4246062 PMID 25278503 a b c d De Silva D Tu YT Amunts A Fontanesi F Barrientos A 2015 07 18 Mitochondrial ribosome assembly in health and disease Cell Cycle 14 14 2226 2250 doi 10 1080 15384101 2015 1053672 PMC 4615001 PMID 26030272 Robles P Quesada V December 2017 Emerging Roles of Mitochondrial Ribosomal Proteins in Plant Development International Journal of Molecular Sciences 18 12 2595 doi 10 3390 ijms18122595 PMC 5751198 PMID 29207474 a b c d De Silva D Tu YT Amunts A Fontanesi F Barrientos A 2015 07 18 Mitochondrial ribosome assembly in health and disease Cell Cycle 14 14 2226 2250 doi 10 1080 15384101 2015 1053672 PMC 4615001 PMID 26030272 Robles P Quesada V December 2017 Emerging Roles of Mitochondrial Ribosomal Proteins in Plant Development International Journal of Molecular Sciences 18 12 2595 doi 10 3390 ijms18122595 PMC 5751198 PMID 29207474 Further reading editGreber BJ Ban N June 2016 Structure and Function of the Mitochondrial Ribosome Annual Review of Biochemistry 85 103 132 doi 10 1146 annurev biochem 060815 014343 PMID 27023846 nbsp This molecular or cell biology article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Mitochondrial ribosome amp oldid 1189875494, wikipedia, wiki, book, books, library,

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