Glauco Tocchini-Valentini

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Glauco P. Tocchini-Valentini is an Italian molecular biologist. As of 2009, he was elected as a foreign associate of the National Academy of Sciences, affiliated with the National Research Council of Italy (CNR). [1] In his forty plus years in molecular biology, he has published over 140 papers on topics like mutagenesis, RNA molecules, structure, function and evolution, disease models, neurodegenerative diseases, and cognitive disorders. [1] He currently resides in Rome, Italy as director at the Institute of Cell Biology. He is also the coordinator for European Mouse Mutant Archive, also known as EMMA. [2] Currently, he is actively advocating advancement in infrastructure for science buildings across Europe.

Contents

Early life and education

Tocchini-Valentini graduated the University Rome La Sapienza in 1959, interested in producing special phosphates in order to synthesize RNA. He pursued his interests at the Karlsruhe Institute of Technology in Karlsruhe, Germany, where he became a radiobiologist in their Institute of Radiology. [3] At the end of his fellowship, Tocchini-Valentini went on teach at the University of Chicago, where he published numerous papers on asymmetrical transcription in collaboration with Franco Graziosi, Peter Geiduschek, Robert Haselkorn, and Samuel Weiss. After leaving University of Chicago in 1996, he returned to Italy, where he is currently affiliated with the National Research Council of Italy.

Research interests

Glauco Tocchini-Valentini's early research focused on demonstrating genetic transcription as an asymmetric process. [4] His publication on findings of asymmetric synthesis of RNA in vitro concluded that the synthesis of mRNA and rRNA is asymmetric whereas DNA yielded symmetric synthesis. [5] From there, he aided in isolating, characterizing, and discovering several enzymes involved in the transcription process, such as DNA and RNA polymerases, rDNA cistrons, and Typell DNA topoisomerase. [6] [7] [8] Much of his work was characterized using various Xenopus laevis cell types, including oocytes, unfertilized eggs, and kidney cells; the characteristics of these amphibian cells and their enzymes were related to mammalian cells and their respective enzymes. [6]

Tocchini-Valentini has also contributed to current understanding of enzyme-substrate rules, stemming from his publication on RNase P and endonuclease from Xenopus laevis cell types. [9] [10] He characterized the tRNA endonucleases of Archaea, finding three forms of tRNA endonuclease. [11] His current research focus is using an archaeal endonuclease (MJ-EndA) to control splicing in both live mice and mice lines. [12] This emergent technology, which can perform both cis- and trans-splicing, allows perturbations to be introduced at the RNA level, thus allowing more specific targeting in mRNA as well as other RNAs. [12] More recently, his research focuses on improving phenotyping data by using "soft windowing." which use adaptive windows of time to include certain controls to result in better analysis across small variations in experiments. [13] He is also involved in the Deep Genome Project, a project which focuses on sequencing all analogous genes in mice as humans in order to better understand disease models and mechanisms. [14] Through phenotyping screens of these mice, genetic components of metabolism and auditory dysfunction has been identified. [15] [16]

Patents

Tocchini-Valentini has filed several patents pertaining to RNA cleavage and recombination. [17] The following two have been approved by the United States Patent and Trademark Office (USPTO): method of RNA cleavage and method of RNA cleavage and recombination.

In 2003, the RNA cleavage method [18] first exposes the target molecule (not containing a tRNA structure [19] ) to a eukaryotic tRNA splicing endonuclease. This puts the molecule in the bulge-helix-bulge conformation, [20] and cleavage occurs in this formation, resulting in cleavage products. The cleavage reaction can occur both in vitro and in vivo, and it is mainly used to demonstrate the presence of specific RNAs in samples. Using fluorescence resonance energy transfer (FRET), the target molecule can be labeled and fluorescence would be measured upon cleavage of the oligonucleotide.

In continuation of this previous patent, he filed a follow up patent in 2004, which was approved on August 20, 2013. [21] As described previously, the RNA molecule is cleaved within the bulge-helix-bulge. As the target RNA molecule and the exogenous RNA molecule are treated with the correct ligase, RNA chimeras form. [22] [23] This results in the recombination of the target RNA and the exogenous RNA across the bulge-helix-bulge structure, thus this method can also be used for recombining RNA molecules in order to alter RNA function and hence gene expression. [24]

Awards and honors

Tocchini-Valentini was awarded the San Giacomo Della Marca Prize in 2007. The San Giacomo della Marca prize is awarded to an esteemed person originating from the Marche area. [25]

Related Research Articles

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Ribonucleic acid (RNA) is a polymeric molecule that is essential for most biological functions, either by performing the function itself or by forming a template for the production of proteins. RNA and deoxyribonucleic acid (DNA) are nucleic acids. The nucleic acids constitute one of the four major macromolecules essential for all known forms of life. RNA is assembled as a chain of nucleotides. Cellular organisms use messenger RNA (mRNA) to convey genetic information that directs synthesis of specific proteins. Many viruses encode their genetic information using an RNA genome.

A restriction enzyme, restriction endonuclease, REase, ENase orrestrictase is an enzyme that cleaves DNA into fragments at or near specific recognition sites within molecules known as restriction sites. Restriction enzymes are one class of the broader endonuclease group of enzymes. Restriction enzymes are commonly classified into five types, which differ in their structure and whether they cut their DNA substrate at their recognition site, or if the recognition and cleavage sites are separate from one another. To cut DNA, all restriction enzymes make two incisions, once through each sugar-phosphate backbone of the DNA double helix.

<span class="mw-page-title-main">RNA splicing</span> Process in molecular biology

RNA splicing is a process in molecular biology where a newly-made precursor messenger RNA (pre-mRNA) transcript is transformed into a mature messenger RNA (mRNA). It works by removing all the introns and splicing back together exons. For nuclear-encoded genes, splicing occurs in the nucleus either during or immediately after transcription. For those eukaryotic genes that contain introns, splicing is usually needed to create an mRNA molecule that can be translated into protein. For many eukaryotic introns, splicing occurs in a series of reactions which are catalyzed by the spliceosome, a complex of small nuclear ribonucleoproteins (snRNPs). There exist self-splicing introns, that is, ribozymes that can catalyze their own excision from their parent RNA molecule. The process of transcription, splicing and translation is called gene expression, the central dogma of molecular biology.

<i>Xenopus</i> Genus of amphibians

Xenopus is a genus of highly aquatic frogs native to sub-Saharan Africa. Twenty species are currently described within it. The two best-known species of this genus are Xenopus laevis and Xenopus tropicalis, which are commonly studied as model organisms for developmental biology, cell biology, toxicology, neuroscience and for modelling human disease and birth defects.

Oligonucleotides are short DNA or RNA molecules, oligomers, that have a wide range of applications in genetic testing, research, and forensics. Commonly made in the laboratory by solid-phase chemical synthesis, these small fragments of nucleic acids can be manufactured as single-stranded molecules with any user-specified sequence, and so are vital for artificial gene synthesis, polymerase chain reaction (PCR), DNA sequencing, molecular cloning and as molecular probes. In nature, oligonucleotides are usually found as small RNA molecules that function in the regulation of gene expression, or are degradation intermediates derived from the breakdown of larger nucleic acid molecules.

<span class="mw-page-title-main">Spliceosome</span> Molecular machine that removes intron RNA from the primary transcript

A spliceosome is a large ribonucleoprotein (RNP) complex found primarily within the nucleus of eukaryotic cells. The spliceosome is assembled from small nuclear RNAs (snRNA) and numerous proteins. Small nuclear RNA (snRNA) molecules bind to specific proteins to form a small nuclear ribonucleoprotein complex, which in turn combines with other snRNPs to form a large ribonucleoprotein complex called a spliceosome. The spliceosome removes introns from a transcribed pre-mRNA, a type of primary transcript. This process is generally referred to as splicing. An analogy is a film editor, who selectively cuts out irrelevant or incorrect material from the initial film and sends the cleaned-up version to the director for the final cut.

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<span class="mw-page-title-main">Transfer RNA</span> RNA that facilitates the addition of amino acids to a new protein

Transfer RNA is an adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length, that serves as the physical link between the mRNA and the amino acid sequence of proteins. Transfer RNA (tRNA) does this by carrying an amino acid to the protein-synthesizing machinery of a cell called the ribosome. Complementation of a 3-nucleotide codon in a messenger RNA (mRNA) by a 3-nucleotide anticodon of the tRNA results in protein synthesis based on the mRNA code. As such, tRNAs are a necessary component of translation, the biological synthesis of new proteins in accordance with the genetic code.

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The Lariat capping ribozyme is a ~180 nt ribozyme with an apparent resemblance to a group I ribozyme. It is found within a complex type of group I introns also termed twin-ribozyme introns. Rather than splicing, it catalyses a branching reaction in which the 2'OH of an internal residue is involved in a nucleophilic attack at a nearby phosphodiester bond. As a result, the RNA is cleaved at an internal processing site (IPS), leaving a 3'OH and a downstream product with a 3 nt lariat at its 5' end. The lariat has the first and the third nucleotide joined by a 2',5' phosphodiester bond and is referred to as 'the lariat cap' because it caps an intron-encoded mRNA. The resulting lariat cap seems to contribute by increasing the half-life of the HE mRNA, thus conferring an evolutionary advantage to the HE.

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References

  1. 1 2 "Member Directory". National Academy of Sciences. Retrieved 4 April 2020.
  2. ↑ Tocchini-Valentini, Glauco (11–13 November 2014). "EMMA - INFRAFRONTIER - IMPC Monterotondo Mouse Clinic (MMC)". IMPC Annual Meeting, Barcelona. POSTER.
  3. ↑ Tocchini-Valentini, Glauco. Personal Letter. https://www.lucacavallisforza.com/wp-content/uploads/2019/09/Memory-Glauco-Tocchini-Valentini.pdf
  4. ↑ Geiduschek, E. Peter; Tocchini-Valentini, Glauco P.; Sarnat, Marlene T. (August 1964). "Asymmetric Synthesis of RNA in Vitro: Dependence of DNA Continuity and Conformation". Proceedings of the National Academy of Sciences of the United States of America. 52 (2): 486–493. Bibcode:1964PNAS...52..486G. doi: 10.1073/pnas.52.2.486 . ISSN   0027-8424. PMC   300303 . PMID   14206614.
  5. ↑ Colvill, A. J.; Kanner, L. C.; Tocchini-Valentini, G. P.; Sarnat, M. T.; Geiduschek, E. P. (May 1965). "Asymmetric RNA synthesis in vitro: heterologous DNA-enzyme systems; E. coli RNA polymerase". Proceedings of the National Academy of Sciences of the United States of America. 53 (5): 1140–1147. Bibcode:1965PNAS...53.1140C. doi: 10.1073/pnas.53.5.1140 . ISSN   0027-8424. PMC   301385 . PMID   4958034.
  6. 1 2 Tatò, F.; Gandini, D. A.; Tocchini-Valentini, G. P. (September 1974). "Major DNA polymerases common to different Xenopus laevis cell types". Proceedings of the National Academy of Sciences of the United States of America. 71 (9): 3706–3710. Bibcode:1974PNAS...71.3706T. doi: 10.1073/pnas.71.9.3706 . ISSN   0027-8424. PMC   433845 . PMID   4530330.
  7. ↑ Mattoccia, E.; Baldi, M. I.; Carrara, G.; Fruscoloni, P.; Benedetti, P.; Tocchini-Valentini, G. P. (November 1979). "Separation of RNA transcription and processing activities from X. laevis germinal vesicles". Cell. 18 (3): 643–648. doi:10.1016/0092-8674(79)90119-3. ISSN   0092-8674. PMID   519751. S2CID   42075603.
  8. ↑ Crippa, M.; Tocchini-Valentini, G. P. (1970-06-27). "Performance of a bacterial RNA polymerase factor in an amphibian oocyte". Nature. 226 (5252): 1243–1244. Bibcode:1970Natur.226.1243C. doi:10.1038/2261243a0. ISSN   0028-0836. PMID   4912321. S2CID   4251098.
  9. ↑ Carrara, G.; Calandra, P.; Fruscoloni, P.; Tocchini-Valentini, G. P. (1995-03-28). "Two helices plus a linker: a small model substrate for eukaryotic RNase P". Proceedings of the National Academy of Sciences of the United States of America. 92 (7): 2627–2631. Bibcode:1995PNAS...92.2627C. doi: 10.1073/pnas.92.7.2627 . ISSN   0027-8424. PMC   42271 . PMID   7708695.
  10. ↑ Doria, M.; Carrara, G.; Calandra, P.; Tocchini-Valentini, G. P. (1991-05-11). "An RNA molecule copurifies with RNase P activity from Xenopus laevis oocytes". Nucleic Acids Research. 19 (9): 2315–2320. doi:10.1093/nar/19.9.2315. ISSN   0305-1048. PMC   329436 . PMID   1710353.
  11. ↑ Tocchini-Valentini, Giuseppe D.; Fruscoloni, Paolo; Tocchini-Valentini, Glauco P. (2005-06-21). "Structure, function, and evolution of the tRNA endonucleases of Archaea: an example of subfunctionalization". Proceedings of the National Academy of Sciences of the United States of America. 102 (25): 8933–8938. Bibcode:2005PNAS..102.8933T. doi: 10.1073/pnas.0502350102 . ISSN   0027-8424. PMC   1157037 . PMID   15937113.
  12. 1 2 Putti, Sabrina; Calandra, Patrizia; Rossi, Nicoletta; Scarabino, Daniela; Deidda, Giancarlo; Tocchini-Valentini, Glauco P. (September 2013). "Highly efficient, in vivo optimized, archaeal endonuclease for controlled RNA splicing in mammalian cells". FASEB Journal. 27 (9): 3466–3477. doi: 10.1096/fj.13-231993 . ISSN   1530-6860. PMID   23682120. S2CID   6486064.
  13. ↑ Haselimashhadi, Hamed; Mason, Jeremy C.; Munoz-Fuentes, Violeta; López-Gómez, Federico; Babalola, Kolawole; Acar, Elif F.; Kumar, Vivek; White, Jacqui; Flenniken, Ann M.; King, Ruairidh; Straiton, Ewan (2020-03-01). "Soft windowing application to improve analysis of high-throughput phenotyping data". Bioinformatics. 36 (5): 1492–1500. doi:10.1093/bioinformatics/btz744. ISSN   1367-4811. PMC   7115897 . PMID   31591642.
  14. ↑ Lloyd, K. & Adams, David & Baynam, Gareth & Beaudet, Arthur & Bosch, Fatima & Boycott, Kym & Braun, Robert & Caulfield, Mark & Cohn, Ronald & Dickinson, Mary & Dobbie, Michael & Flenniken, Ann & Flicek, Paul & Galande, Sanjeev & Gao, Xiang & Grobler, Anne & Heaney, Jason & Herault, Yann & Angelis, Martin & Brown, Steve. (2020). The Deep Genome Project. Genome Biology. 21. 18. 10.1186/s13059-020-1931-9.
  15. ↑ Bowl, Michael R.; Simon, Michelle M.; Ingham, Neil J.; Greenaway, Simon; Santos, Luis; Cater, Heather; Taylor, Sarah; Mason, Jeremy; Kurbatova, Natalja; Pearson, Selina; Bower, Lynette R. (12 October 2017). "A large scale hearing loss screen reveals an extensive unexplored genetic landscape for auditory dysfunction". Nature Communications. 8 (1): 886. Bibcode:2017NatCo...8..886B. doi:10.1038/s41467-017-00595-4. ISSN   2041-1723. PMC   5638796 . PMID   29026089.
  16. ↑ Rozman, Jan; Rathkolb, Birgit; Oestereicher, Manuela A.; Schütt, Christine; Ravindranath, Aakash Chavan; Leuchtenberger, Stefanie; Sharma, Sapna; Kistler, Martin; Willershäuser, Monja; Brommage, Robert; Meehan, Terrence F. (18 January 2018). "Identification of genetic elements in metabolism by high-throughput mouse phenotyping". Nature Communications. 9 (1): 288. Bibcode:2018NatCo...9..288R. doi:10.1038/s41467-017-01995-2. ISSN   2041-1723. PMC   5773596 . PMID   29348434.
  17. ↑ "Patents by Inventor Glauco P. Tocchini-Valentini". JUSTIA. August 20, 2013. Retrieved 18 April 2020.
  18. ↑ Publication number: 20040023239 Type: Application Filed: Jan 7, 2003 Publication Date: Feb 5, 2004 Inventors: Glauco P. Tocchini-Valentini (Rome), Giancarlo Deidda (Rome), Nicoletta Rossi (Rome), Maria Irene Baldi (Rome), Paolo Fruscoloni (Rome) Application Number: 10296574
  19. ↑ Bufardeci, E., Fabbri, S., Baldi, M. I., Mattoccia, E. and Tocchini-Valentini, G. P., “in vitro genetic analysis of the structural features of the pre-tRNA required for determination of the 3′ splice site in the intron excision reaction,” EMBO J. 12:46974704 (1993).
  20. ↑ Gandini-Attardi, D., Margarit, I. and Tocchini-Valentini, G. P., “Structural alteration in mutant precursors of the yeast tRNALeu3 gene which behave as defective substrates for a highly purified splicing endoribonuclease,” EMBO J. 4:3289-3297 (1985).
  21. ↑ "US Patent for Method of RNA cleavage and recombination Patent (Patent # 8,512,945 issued August 20, 2013) - Justia Patents Search". patents.justia.com. Retrieved 2020-04-19.
  22. ↑ Perkins, K. K., Furneaux, H. and Hurwitz, J., “Isolation and characterization of an RNA ligase from HeLa cells,” Proc. Natl. Acad. Sci. USA 82:684-688 (1985).
  23. ↑ Mattoccia, E., Baldi, M. I., Gandini-Attardi, D., Ciafrè, S. and Tocchini-Valentini, G. P., “Site selection by the tRNA splicing endonuclease of Xenopus laevis,” Cell 55:731-738 (1988)
  24. ↑ Patent number: 8512945 Type: Grant Filed: Apr 9, 2004 Date of Patent: Aug 20, 2013 Patent Publication Number: 20050043259 Inventors: Glauco P. Tocchini-Valentini (Rome), Giancarlo Deidda (Rome), Nicoletta Rossi (Rome) Primary Examiner: Dana Shin Application Number: 10/821,777
  25. ↑ Ferrazzoli, Marco (November 11, 2001). "Sarnano: a Glauco Tocchini Valentini il Premio San Giacomo della Marca". Vivere Marche. Retrieved March 8, 2020.
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