FIND ARTICLE

MOLECULAR BASIS OF REPLICATION AND ENDOREDUPLICATION

Formation of cells with a duplicated genome may be a consequence of endomitosis, incomplete mitosis or endoreduplication. During endoreduplication, nuclear DNA is replicated without entering mitosis. In mammals it gives rise to trophoblast cells with extra copies of the genomic DNA, but in the animal world endoreduplication is the most widespread in insects. Multiple rounds of endoreduplication cycles produce cells with nuclei with 8C, 16C, 32C (etc.) DNA contents. To make it happen, cells must escape the mechanisms that prevent another round of replication.

AFFLICTIONS OF LAMINS’ FUNCTIONS AND THE PATHOPHYSIOLOGY OF LAMINOPATHIES

Lamins are components of nucleus, which not only influence organization and integrity of nuclear envelope, but are also essential for the maintenance and processing of genetic material. Therefore, disturbance of their functioning as a result of mutations in various regions of the protein molecule can have serious consequences for the number and activity of cells in various tissues. Since identifying lamin defects as important factors in a vast range of diseases, research aimed at elucidation of tissue-specific mechanisms in the pathophysiology of particular syndroms has been in progress.

CYTOSKELETAL ACTIN STRUCTURES FORMED AT THE LEADING EDGE OF THE MIGRATING CELL DURING THE FIRST STEP OF MIGRATION

Protrusion of the leading edge represents the first step of cell migration. This process is connected with formation of cytoskeletal actin-containing structures called lamellipodia and filopodia. Reorganization of cortical actin filaments in response to extracellular stimuli is controlled by The Wiskott- Aldrich syndrome proteins (WASP), a protein family members that are believed to be important effectors of Rho GTPases and to mediate in activating Arp2/3 (actin-related protein 2-3) complex.

The Editorial Board
Andrzej Łukaszyk - przewodniczący, Zofia Bielańska-Osuchowska, Szczepan Biliński, Mieczysław Chorąży, Aleksander Koj, Włodzimierz Korochoda, Leszek Kuźnicki, Aleksandra Stojałowska, Lech Wojtczak

Editorial address:
Katedra i Zakład Histologii i Embriologii Uniwersytetu Medycznego w Poznaniu, ul. Święcickiego 6, 60-781 Poznań, tel. +48 61 8546453, fax. +48 61 8546440, email: mnowicki@ump.edu.pl

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