RESUMO
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a well-studied glycolytic protein with energy production as its implied occupation. It has established itself lately as a multifunctional protein. Recent studies have found GAPDH to be involved in a variety of nuclear and cytosolic pathways ranging from its role in apoptosis and regulation of gene expression to its involvement in regulation of Ca2+ influx from endoplasmic reticulum. Numerous studies also indicate that GAPDH interacts with microtubules and participates in cell membrane fusion. This review is focused on the cytosolic functions of the protein related to vesicular transport. Suggestions for future directions as well as the model of protein polymer structure and possible post-translational modifications as a basis for its multifunctional activities in the early secretory pathway are given.
Assuntos
Retículo Endoplasmático/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/fisiologia , Complexo de Golgi/metabolismo , Vesículas Transportadoras/metabolismo , Animais , Transporte Biológico/fisiologia , Humanos , Modelos BiológicosRESUMO
Nuclear accumulation of ODNs has been associated with their binding to a series of nuclear proteins. These interactions could be responsible for the sequence-independent effects of ODNs as well as for their sequence-specific interactions and their intracellular distribution. Investigation of interaction of ODNs with these proteins may shed light on the mechanisms of cellular uptake and nuclear accumulation of oligonucleotides.
Assuntos
Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Oligonucleotídeos/farmacocinética , Ligação Competitiva , Núcleo Celular/metabolismo , Endotélio/citologia , Endotélio/enzimologia , Endotélio/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/antagonistas & inibidores , Células HeLa , Humanos , Monócitos/enzimologia , Monócitos/metabolismo , Oligonucleotídeos/farmacologiaRESUMO
In vivo stability and distribution of deoxyribooligonucleotides and 3'-end modified oligodeoxyribooligonucleotides were studied in blood serum and cells. Substitution of two 3'-end internucleotide phosphodiester bonds increased the stability of modified oligonucleotides. Modified oligonucleotides were shown to be stable in blood serum for up to 24 hours. Leukocytes did not bind oligonucleotides significantly, whereas erythrocytes accumulate mono-, di-, three-, tetranucleotides appeared in the blood stream as degradation products of the parent oligonucleotide.
Assuntos
Oligodesoxirribonucleotídeos Antissenso/farmacocinética , Organotiofosfatos/farmacocinética , Animais , Eritrócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Oligodesoxirribonucleotídeos Antissenso/sangue , Organotiofosfatos/sangueRESUMO
Affinity modification of proteins was used to study their interaction with oligonucleotides barrier fluids. Several proteins of saliva and tears were shown to undergo affinity modification during incubation with an alkylating derivative of deoxyribooligonucleotides. In tears, such proteins were lactoferrin, immunoglobin G and lysozyme; in saliva, immunoglobulin A and lysozyme. The data showed that the affinity for oligonucleotides decrease in the order lactoferrin > lysozyme > immunoglobulin A > immunoglobulin G. The binding of reactive oligonucleotide derivatives with the proteins was competitively inhibited by polyanions, such as oligonucleotides of various nucleotide compositions, single-stranded and double-stranded DNA, heparin, and dextran sulfate. Interactions between oligonucleotides and proteins can strongly affect the metabolism of oligonucleotides and their ability to permeate biological barriers.
