Protein translation

Phát triển là quá trình kiểm soát sự biểu hiện gen, quá trình điều hòa phức tạp về cơ chế, cơ bản có 5 mức độ: 1- Sự xoắn của NST (Chromatin Packing) 2- Kiểm soát sự phiên mã (Transcriptional Control) 3- Điều hòa hậu phiên mã (Posttranscriptional) [Nhân tế bào (Nuclear levels)] 4- Kiểm soát sự giải mã (Translational Control) 5- Điều hòa hậu giải mã (Posttranslational Control) [Cytosol (Cytoplasmic levels)] Sự điều hòa phiên mã bởi những phân tử protein,yếu tố phiên mã (transcription factors -TF). Các phân tử protein này luôn hiện diện trong tế bào và bám...

62p bichtram1910 22-05-2012 249 38   Download

 Bài giảng Sinh tổng hợp protein (protein translation) cung cấp cho người học các kiến thức cơ bản của sinh tổng hợp protein như một số khái niệm cơ bản của quá trình dịch mã, giai đoạn khởi đầu của quá trình dịch mã ở prokaryote, giai đoạn kéo dài của quá trình dịch mã ở prokaryote, giai đoạn kết thúc của quá trình dịch mã ở prokaryote, giai đoạn khởi đầu của quá trình dịch mã ở eukaryote, giai đoạn kéo dài của quá trình dịch mã ở eukaryote, giai đoạn kết thúc của quá trình dịch mã ở eukaryote.

45p kianh88 05-05-2015 423 79   Download

Phần 2 bài giảng về "Sinh tổng hợp protein (Protein translation)" gồm có nhứng nội dung chính sau: Giai đoạn khởi đầu của quá trình dịch mã ở eukaryote, giai đoạn kéo dài của quá trình dịch mã ở eukaryote, giai đoạn kết thúc của quá trình dịch mã ở eukaryote. Mời các bạn cùng tham khảo.

30p tieu_vu16 03-01-2019 96 7   Download

Chương này trình bày đến người học: Một số khái niệm cơ bản của quá trình dịch mã, sự dịch mã của mRNA, giai đoạn khởi đầu của quá trình dịch mã ở prokaryote, giai đoạn kéo dài của quá trình dịch mã ở prokaryote, giai đoạn kết thúc của quá trình dịch mã ở prokaryote. Mời các bạn cùng tham khảo.

31p tieu_vu16 03-01-2019 49 4   Download

Bài giảng Sinh học phân tử: Chương 5 Quá trình sinh tổng hợp Protein, cung cấp cho người học những kiến thức như: RNA thông tin (mRNA); Cấu trúc RNA vận chuyển; Đột biến làm thay đổi khung đọc; Quá trình dịch mã (Translation); Sự phân tách của Ribosome;...Mời các bạn cùng tham khảo!

35p caphesuadathemmatong 25-11-2021 33 3   Download

The signaling properties of the gasotransmitter molecule hydrogen sulfide (H2S), which is endogenously generated in plant cells, are mainly observed during persulfidation, a protein post-translational modification (PTM) that affects redox-sensitive cysteine residues. There is growing experimental evidence that H2S in higher plants may function as a mechanism of response to environmental stress conditions.

7p partimesinhvien 08-05-2020 31 0   Download

We have examined the effects of widely used stress-inducing agents on protein synthesis and on regulatory components of the translational machinery. The three stresses chosen, arsenite, hydrogen peroxide and sorbitol, exert their effects in quite different ways. Nonetheless, all three rapidly ( 30 min) caused a profound inhibition of protein synthesis. In each case this was accompanied by dephosphorylation of the eukaryotic initiation factor (eIF) 4E-binding protein 1 (4E-BP1) and increased binding of this repressor protein to eIF4E. ...

10p system191 01-06-2013 44 4   Download

The long uORF-burdened 5¢UTRs of many genes encoding regulatory proteins involved in cell growth and differentiation contain internal ribosomal entry site (IRES) elements. In a previous study we showed that utilization of the weak IRES of platelet-derived growth factor (PDGF2) is activated during megakaryocytic differentiation.

10p system191 01-06-2013 34 4   Download

Transglutaminase (TGase) catalyses the post-translational modification of proteins by transamidation of available glutamine residues. While several TGase genes of fish and arthropods have been cloned and appear to have similar structures to those of mammals, no homologous gene has been found in lower eukaryotes. We have cloned the acellular slime mold Physarum polycephalum TGase cDNA using RT-PCR with degenerated primers, based on the partial amino acid sequence of the purified enzyme. The cDNA contained a 2565-bp ORF encoding a 855-residue polypeptide.

10p research12 01-06-2013 48 4   Download

A systematic search for Escherichia coli proteins with the zinc-binding activity was performed using the assay of radioactive Zn(II) binding to total E. coli proteins fractionated by two methods of two-dimensional gel electrophoresis. A total of 30–40 radioactive spots were identified, of which 14 have been assigned from N-terminal sequencing.

11p research12 01-06-2013 35 3   Download

The structure of post-translational modifications of human heparin cofactor II isolated from human serum and from recombinant Chinese hamster ovary cells and their effects on heparin binding have been characterized. Oligosaccharide chains were found attached to all three potential N-glycosylation sites in both protein preparations. The carbohydrate structures of heparin cofactor II circulating in blood are complex-type diantennary and triantennary chains in a ratio of 6 : 1 with the galactose being 90% sialylated with a2 fi 6 linked N-acetylneuraminic acid....

12p research12 01-06-2013 44 3   Download

Multimolecular complexes involving the eukaryotic elongation factor 1A (eEF1A) have been suggested to play an important role in the channeling (vectorial transfer) of tRNAduring protein synthesis [Negrutskii, B.S.&El’skaya, A.V. (1998)Prog. Nucleic Acids Res. Mol. Biol.60,47–78]. Recently we have demonstrated that besides performing its canonical function of forming a ternary complex with GTP and aminoacyl-tRNA, the mammalian eEF1A can produce a noncanonical ternary complex with GDP and uncharged tRNA [Petrushenko, Z.M., Negrutskii, B.S.,...

8p research12 29-04-2013 40 3   Download

The estrogen receptor-related receptorc (ERRc/ERR3/ NR3B3) is an orphan member of the nuclear receptor superfamily closely related to the estrogen receptors. To explore the DNA binding characteristics, the protein–DNA interaction was studied in electrophoretic mobility shift assays (EMSAs). In vitro translated ERRc binds as a homodimer to direct repeats (DR) without spacing of the nuclear receptor half-site 5¢-AGGTCA-3¢(DR-0), to exten-dedhalf-sites, and to the inverted estrogen response element....

12p research12 23-04-2013 23 3   Download

Protein synthesis requires both amino acids, as precursors, and a substantial amount of metabolic energy. It is well established that starvation or lack of nutrients impairs pro-tein synthesis in mammalian cells and tissues. Branched chain amino acids are particularly effective in promoting protein synthesis. Recent work has revealed important new information about the mechanisms involved in these effects. Anumber of components of the translational machinery are regulated through signalling events that require the mam-malian target of rapamycin, mTOR. ...

12p tumor12 22-04-2013 35 2   Download

Eukaryotic initiation factor 4E (eIF4E) plays an important role inmRNA translation by binding the 5¢-cap structure of themRNAand facilitating the recruitment to themRNAof other translation factors and the 40S ribosomal subunit. eIF4E can interact either with the scaffold protein eIF4Gor withrepressor proteins termed eIF4E-binding proteins (4E-BPs). Highlevels of expression can disrupt cellular growthcontrol and are associated withhuman cancers.

10p tumor12 22-04-2013 37 2   Download

The elongation phase of mRNA translation is the stage at which the polypeptide is assembled and requires a substantial amount of metabolic energy. Translation elongation in mammals requires a set of nonribosomal proteins called eukaryotic elongation actors or eEFs. Several of these proteins are subject to phosphorylation in mammalian cells, including the factors eEF1A and eEF1B that are involved in recruitment of amino acyl-tRNAs to the ribosome.

9p tumor12 22-04-2013 35 2   Download

E2F transcription factors play an important role in the regulation of cell cycle progression. E2F6, the most recently identified member of the E2F family, is a retinoblastoma-protein-independent transcriptional repressor that is required for developmental patterning of the axial skeleton. It has recently been shown that theE2f6locus produces two different mRNAs, E2F6 and E2F6b. The E2F6b mRNA contains an additional exon that is inserted by alternative splicing.

7p tumor12 22-04-2013 32 1   Download

The phylogenetically conserved eukaryotic translation initi-ation factor 5A(eIF5A) is the onlyknown cellular protein to contain thepost-translationallyderivedaminoacidhypusine [N e -(4-amino-2-hydroxybutyl)lysine]. Both eIF5A and its hypusine modification are essential for sustained cell proli-feration. Normally only one eIF5A protein is expressed in human cells. Recently, we identified a second humanEIF5A gene that would encode an isoform (eIF5A-2) of 84% sequence identity.

10p tumor12 20-04-2013 42 3   Download

Mammalian translation initiation factor 3 (eIF3) is a multisubunit complex containingat least 12 subunitswithan apparent aggregate mass of
700 kDa.eIF3 binds to the 40S ribosomal subunit, promotes the binding of methionyl-tRNA i and mRNA, and interacts with several other initi-ation factors to form the 40S initiation complex.Human cDNAs encoding 11 of the 12 subunits have been isolated previously; here we report the cloning and characterization of a twelfth subunit, a 28-kDa protein named eIF3k.Evi-dence that eIF3k is present in the eIF3 complex was obtained....

7p tumor12 20-04-2013 33 3   Download

N-tert-Butyl-N,N¢-dibenzoylhydrazine and its analogs are nonsteroidal ecdysone agonists that exhibit insect molting hormonal and larvicidal activities. The interaction mode of those ecdysone agonists with the heterodimer of the ecdy-sone receptor andultraspiracle has not been fully elucidated. We expressed the ecdysone receptor B1 and the ultraspiracle of the lepidopteran,Chilo suppressalis,using anin vitro transcription/translation system and confirmed, using gel-shift assays, that the proteins functionas ecdysone receptors. We also analyzed their ligand-binding affinity. ...

10p tumor12 20-04-2013 46 3   Download