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INTEINY
- BUDOWA,
FUNKCJE
BIOLOGICZNE
I
FILOGENEZA
Liliana
Serwecińska, Paweł Stączek,
Adam
Jaworski
1. Wprowadzenie.
2. Nazewnictwo, rodzaje i rozpowszechnienie intein. 3. Ukierunkowane
endonukleazy intein. 4. Obecność
intein w białkach metabolizmu DNA. 5. Rozważania na temat
funkcji i pochodzenia
intein. 6. Zastosowanie intein w biotechnologii
Inteins -
organization, biological functions and phylogenesis
Abstract
Inteins
are the intervening sequences of proteins that are excised
from precursor by an auto-catalytic
mechanism. The regions flanking an intein are called exteins.
Inteins in contrast to introns, are transcribed and
translated together with their host protein. Most of these
elements consist of two domains:
one that catalyzes its own removal from the host protein and is
involved in protein self-splicing,
and the other display a site-specific endonuclease activity.
Posttranslational highly specific self-cleavage of intein,
and protein ligation reactions lead to the splicing of functional
protein in the cell. Inteins avoid disrupting their host gene
function by splicing themselves out at the protein level. Endonucleases of inteins are rare-cutting enzymes that
confer genetic mobility to these elements by catalyzing a specific double-strand break in a cognate recipient
allele of the host gene lacking intein. The end result
of such homing process is the duplication of the intein. Inteins
occur in all three kingdoms of life:
archea, eubacteria, and eukaryote. This broad phylogenetic
distribution suggest their ancient
evolutionary origin, and reflects their naturę as a mobile
genetic elements. Also, cases of horizontał inteins
transfer have been discovered. Inteins exist in numerous host
protein, many of these proteins
arę involved in DNA replication, transcription, and repair
mechanisms, although there is no known
limitation on the type of host protein. Inteins provide a source
for innovate biotechnology tools, particulary
for protein purification, for labeling or protein modification,
and for cytotoxins expression.
1. Introduction.
2. Nomenclature, types and dissemination of inteins. 3. Homing
endonucleases. 4. Localization
of inteins in DNA metabolism proteins. 5. Inteins function
and origin. 6. Application of intein systems |
