| (1) Establishment for methods for extraction, separation and structural determination
of endogenous peptides (Scheme) |
| 1. Establishment for methods for extraction, separation and structural determination
of endogenous peptides |
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In order to establish the methods required for constructing the fact database
for endogenous peptides, we will develop
- the optimal extraction procedures for the peptides in the tissue and cells
by minimizing the degradation of peptides and proteins,
- the efficient and quick condensation procedures for the peptide fraction
of Mr less than 6,000,
- the normalized 2-dimensional high performance liquid chromatography (2D-HPLC)
for the separation of the peptide fraction,
- the detection and structural analysis methods for the peptides mainly using
mass spectrometers, and
- the data acquisition system for the physicochemical properties (hydrophobicity,
positive charges, and molecular mass) of the peptides during the separation,
detection and analysis steps.
These procedures and systems should be normalized, automated and highly
sensitive to obtain the data enough for the Peptidome database.
(Invetigator) |
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| 2. High-sensitivity structural analysis of biological peptides by mass
spectrometry |
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Mass spectrometric (MS) methods and relating techniques for high-sensitivity
and high-throughput analysis of biological peptides are under study and
the following results have been obtained:
- MS/MS sequencing of peptides using picomole level of samples,
- High-throughput N-terminal sequencing (up to three amino acid residues)
by combination of gas-phase chemical reaction and matrix-assisted laser
desorption ionization MS
- Development of a stable isotope-labeling method for "Peptidomics",
- Identification of several MS/MS fragment ions characteristic for the modified
peptides such as those containing methionine sulfoxide, phosphorylated
amino acid and beta-aspartic acid,
- Improvement of software aid for peptide sequencing based on MS/MS (http://www.protein.osaka-u.ac.jp/organic/),
and
- Development of a search engine based on MS data to aid peptide identification
from sequence databases by MS.
(Invetigator) |
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| (2) Biological activities and structure of endogenous peptides and receptors (Scheme) |
| 1. Highly efficient discovery system for biologically active peptides using
cultured cells and orphan G protein-coupled receptors |
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This sub-theme is aimed to develop the efficient, systematic and highly
sensitive methods that are required for screening and identifying new biologically
active peptides. To detect even weak biological activity in the screening,
we will set up the high throughput and sensitive system for measurements
of the second messenger concentrations (intracellular calcium and cAMP)
in the cultured cells as well as in the cells expressing orphan G-protein
coupled receptors. By using these systems, we will search for new biologically
active peptides in the extracts of porcine and rat tissue extracts, and
analyze their functions when the peptides are identified. During the screening
steps, we will also comprehensively collect the screening data and store
them on the common platform (normalized 2D-HPLC) of the Peptidome database.
(Invetigator) |
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| 2. Isolation and characterization of bioactive peptides using functional
nd developmental assay systems |
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Biologically active peptides interact with functional proteins (e.g. receptors,
ion channels, enzymes etc.), and they are critically involved in controlling
cellular signal transduction, metabolism and development. To unveil such
peptides, we developed a sensitive and high-throughput screening system
using cells expressing specific functional protein or cells of potential
development. Molecular and physiological information of the peptides identified
using the system is to be deposited to the peptide database of this project.
(Invetigator) |
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| 3. Sensitive and high throughput ligand-screening system of G protein-coupled
receptors. |
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The ligand-screening system for G protein-coupled receptors will be developed
and used for identification of peptides as endogenous ligands for orphan
G protein-coupled receptors.
(Invetigator) |
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| 4. Structural modeling of peptides and peptide receptors for drug design |
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This project focuses on elucidation of the receptor-bound structures of
bioactive peptides. We apply molecular dynamics simulations and NMR analysis
to elucidation of the solution structures of bioactive peptides. Modeling
of the “active form” of peptide receptors from the rhodopsin crystal
structure is also a major interest in modeling the receptor-bound structures
of the bioactive peptides. Those structural data will be used for designing
new peptide analogs and nonpeptide molecules.
(Investigator) |
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(3) Construction of PEPTIDOME database (Scheme) |
| 1-1. Research on the efficient collection and storage methods of various
peptide information in the Peptidome database |
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The Peptidome database contains various kinds of information, as this is
the fact database based on the results obtained by the experiments and
measurements. Thus , it is essential to develop the database system suitable
for collecting and storing huge amounts of experimental data obtained in
this project, such as mass-spectrum and chromatographic data, natural abundance,
processing, biological activity and receptors of the peptides as well as
the fractions during the separation processes. Researchers should be easily
able to register their results into the database and to search/utilize
them. New general description system for the sequence and modified structure
of peptides will also be set up for the mass spectrometric analysis and
database searching. Moreover, we will also develop the system to get related
information of the target peptides efficiently and quickly from the reference
databases.
(Invetigator) |
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| 1-2. Construction of Peptidome database efficient for searching and discovery |
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To construct the Peptidome database that is easily searched by the researchers,
we will develop the relational fact database, which systematically stores
the different types and huge amounts of data based on the physiocochemical
and other properties of the peptides. We further study the extensibility
of the Peptidome database for the future increments of amounts and diversity
of the peptide data. The data mining and discovery system will also be
developed to deduce unknown activity of the peptides as well as to fill
up the deleted data from the analysis and comparison of the stored peptide
data by maximally utilizing the features of this database.
(Invetigator) |
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| 2. Research for relational system between biological databases. |
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There are hundreds of biological databases in the internet world, which
is maintained independently. To make the 'Peptidome Database' useful for
their users, it is important to fit the database within the network of
biological databases. Linking the URL in WWW system is a useful and well
known method to overcome this issue. An automated system to create this
link during the update of each database, and fitting Peptidome database
to this system is under development. Also, it is important to FEEL the
peptide as they behave in the micro-environment. I am developing a virtual
reality system with force feed back to feel the potential they have.
(Invetigator) |
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