Figure 3. Immunofluorescent localization of procollagen I and Hsp47 in the presence or absence of brefeldin A treatment in CEC. Cells were treated with 2 µg/ml brefeldin A for 30 min, fixed, permeabilized, and stained as described in the text. A. Procollagen I (green) and Hsp47 (red) in brefeldin A-treated cells. B. Prolyl 4-hydroxylase (green) and procollagen I (red) in brefeldin A-treated cells. C. Prolyl 4-hydroxylase (green) and Hsp47 (red) in brefeldin A-treated cells. D. Phase-contrast microscopy of C. Bar, 10 µm.. ...
(His)6-GBF1 is a BFA-resistant ARF-GEF. (A) Fractions enriched in (His)6-GBF1 display a GEF specific for ARFs. Identical volumes (5 μl) of the 50 mM imidazole
brefeldin A esterase: hydrolyzes brefeldin A to brefeldin A acid & also hydrolyzes ethyl valerate; 372 amino acids; amino acid sequence given in first source
In mammalian and yeast cells, the main target of brefeldin A appears to be a guanine nucleotide exchange factor (GEF) called GBF1.[8] GBF1 is a member of the Arf family of GEFs which are recruited to membranes of the Golgi.[9] It is responsible for the regulation of Arf1p GTPase.[9] It does this through converting the inactive GDP-bound form of Arf1p to the active GTP-bound form.[9] The nucleotide exchange occurs at the catalytic Sec7 domain of GBF1. Activated Arf1p then recruits coat protein β-COP, a subunit of the COP-I complex, to cargo-bound receptors on the membrane.[9] Coat protein recruitment is necessary for proper vesicle formation and transport. Brefeldin A reversibly inhibits the function of GBF1 uncompetitively by binding to the complex it forms with GDP-bound Arf1p and preventing conversion to the GTP-bound form.[9] The lack of active Arf1p prevents coat protein recruitment, which then ultimately induces the fusion of neighboring ER and Golgi membranes due to lack of vesicle ...
We examined the actions on ENaC recycling of reagents that alter membrane trafficking and cytoskeletal organization using the restimulation protocol. Treatment with BFA did not affect the first response to forskolin, but it produced a marked inhibition of the subsequent ΔISC. The finding that it was possible to elicit one cycle of forskolin stimulation-recovery suggests that ENaC-containing vesicles available for channel insertion are distal to the Golgi and TGN. The response to restimulation was significantly reduced, however, indicating that ENaC is recycled through BFA-sensitive compartments. Results from a study using BFA-treated toad bladder produced similar findings in response to repeated ADH stimulation; an initial stimulation could be elicited, but subsequent stimulations were abolished by pretreatment with 5 μg/ml BFA (Weng and Wade, 1994). The effect of BFA on ENaC recycling was unexpected in view of its well-documented inhibition of AP-1-dependent trafficking in early compartments ...
Brefeldin A-inhibited guanine nucleotide-exchange protein 3 (BIG3) has been identified recently as a novel regulator of estrogen signalling in breast cancer cells. Despite being a potential target for new breast cancer treatment, its amino acid sequence suggests no association with any well-characterized protein family and provides little clues as to its molecular function. In this paper, we predicted the structure, function and interactions of BIG3 using a range of bioinformatic tools. Homology search results showed that BIG3 had distinct features from its paralogues, BIG1 and BIG2, with a unique region between the two shared domains, Sec7 and DUF1981. Although BIG3 contains Sec7 domain, the lack of the conserved motif and the critical glutamate residue suggested no potential guaninyl-exchange factor (GEF) activity. Fold recognition tools predicted BIG3 to adopt an α-helical repeat structure similar to that of the armadillo (ARM) family. Using state-of-the-art methods, we predicted interaction sites
We recently reported that brefeldin A-inhibited guanine nucleotide-exchange proteins 3 (BIG3) binds Prohibitin 2 (PHB2) in cytoplasm, thereby leading to a reduction of function of the PHB2 growth suppressor in the nuclei of breasts tumor cells. PHB2 nuclear transfer may offer restorative strategies for managing Elizabeth2/Emergency room signs in breasts tumor cells. Introduction Prohibitin 1 and 2 (PHB and buy 808118-40-3 PHB2) proteins are highly conserved in eukaryotic cells and exhibit diverse subcellular localization with different functions [1C3]. These molecules are primarily observed in inner mitochondrial membranes via their buy 808118-40-3 N-terminal transmembrane domain but are also present in several other localizations such as the cytosol, endoplasmic reticulum, nucleus, and plasma membrane [1]. Both proteins form hetero-oligomeric ring structures in the inner mitochondrial membrane and function as chaperones buy 808118-40-3 that maintain mitochondrial integrity and stabilize ...
Arfgef1 (untagged) - Mouse ADP-ribosylation factor guanine nucleotide-exchange factor 1(brefeldin A-inhibited) (Arfgef1), (10ug), 10 µg.
gi,17538522,ref,NP_501092.1, component of oligomeric Golgi complex 2; brefeldin A-sensitive, LDLC related peripheral Golgi protein, required for normal Golgi function; contains an N myristoylation domain (78.6 kD) (4H802) [Caenorhabditis elegans] gi,2498513,sp,Q21444,COG2_CAEEL Conserved oligomeric Golgi complex component 2 (LDLC protein homolog) gi,1078836,pir,,B53542 brefeldin A-sensitive Golgi protein LDLC - Caenorhabditis elegans gi,807871,emb,CAA84428.1, Cog2 protein [Caenorhabditis elegans] ...
The Golgi apparatus has long been suggested to be important for directing secretion to specific sites on the plasma membrane in response to extracellular signaling events. However, the mechanisms by which signaling events are coordinated with Golgi apparatus function remain poorly understood. Here, we identify a scaffolding function for the Golgi matrix protein GM130 that sheds light on how such signaling events may be regulated. We show that the mammalian Ste20 kinases YSK1 and MST4 target to the Golgi apparatus via the Golgi matrix protein GM130. In addition, GM130 binding activates these kinases by promoting autophosphorylation of a conserved threonine within the T-loop. Interference with YSK1 function perturbs perinuclear Golgi organization, cell migration, and invasion into type I collagen. A biochemical screen identifies 14-3-3zeta as a specific substrate for YSK1 that localizes to the Golgi apparatus, and potentially links YSK1 signaling at the Golgi apparatus with protein transport events, cell
There are six subfamilies of Arf GEFs in eukaryotes (see poster). The GBF/Gea and BIG/Sec7 GEFs function sequentially in the secretory pathway, with GBF/Gea proteins acting at the early Golgi, and BIG/Sec7 proteins at the trans-Golgi and TGN (Donaldson and Jackson, 2011). The cytohesin/Arno, EFA6 and IQSEC/BRAG subfamilies function primarily in endosome-plasma-membrane trafficking pathways at the cell periphery, the latter two using Arf6 as a substrate (Casanova, 2007; Gillingham and Munro, 2007). The FBXO8 GEFs, restricted primarily to vertebrates, contain an F-box in addition to the Sec7 domain (Gillingham and Munro, 2007). Arf activation by GBF/Gea and BIG/Sec7 GEFs is inhibited by the drug brefeldin A, which traps a Sec7-domain-Arf-GDP complex (Mossessova et al., 2003; Peyroche et al., 1999; Renault et al., 2003).. Many GEFs exist in an autoinhibited state in the cytosol, with their activation coupled to membrane recruitment. At the plasma membrane, the Pleckstrin homology (PH) domains of ...
The Golgi complex plays a key role in the sorting and modification of proteins exported from the endoplasmic reticulum. The protein encoded by this gene is involved in the maintenance of Golgi structure and function through its interaction with the integral membrane protein giantin. It may also be involved in the hormonal regulation of steroid formation. [provided by RefSeq, Jul 2008 ...
Zinc Finger Protein Containing Five Transmembrane Domains; Null Mutant Exhibits Strongly Fragmented Vacuoles And Sensitivity To Brefeldin A, A Drug Which Is Known To Affect Intracellular Transport
A golgi apparatus, or golgi complex, is the main organelle responsible for mediating the transportation of protein and fat within the cell, according to Scitable, a learning website curated by...
The Golgi apparatus is an organelle found in the cytoplasm of most eukaryotic cells that is involved in the packaging and secretion of substances nece...
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TY - JOUR. T1 - Brefeldin A rapidly disrupts plasma membrane polarity by blocking polar sorting in common endosomes of MDCK cells. AU - Wang, E.. AU - Pennington, J. G.. AU - Goldenring, J. R.. AU - Hunziker, W.. AU - Dunn, Kenneth. PY - 2001. Y1 - 2001. N2 - Recent studies showing thorough intermixing of apical and basolateral endosomes have demonstrated that endocytic sorting is critical to maintaining the plasma membrane polarity of epithelial cells. Our studies of living, polarized cells show that disrupting endocytosis with brefeldin-A rapidly destroys the polarity of transferrin receptors in MDCK cells while having no effect on tight junctions. Brefeldin-A treatment induces tubulation of endosomes, but the sequential compartments and transport steps of the transcytotic pathway remain intact. Transferrin is sorted from LDL, but is then missorted from common endosomes to the apical recycling endosome, as identified by its nearly neutral pH, and association with GFP chimeras of Rabs 11a and ...
FUNCTION: Guanine nucleotide-exchange factor (GEF) required for the formation or budding of transport vesicles from the ER. This function involves the cytoplasmic domain of the protein, which is thought to interact with the small GTP-binding protein SAR1. Required for autophagy. MISCELLANEOUS: In the process of transport, SEC12 itself may migrate to the Golgi apparatus and function in subsequent transport events. MISCELLANEOUS: Present with 6160 molecules/cell in log phase SD medium ...
Background: In hepatocytes and alcohol-metabolizing cultured cells, Golgi undergoes ethanol (EtOH)-induced disorganization. Periniclear and organized Golgi is important in liver homeostasis, but how the Golgi remains intact is unknown. Work from our laboratories showed that EtOH-altered cellular function could be reversed after alcohol removal; we wanted to determine whether this recovery would apply to Golgi. Methods: We used alcohol-metabolizing HepG2 (VA-13) cells (cultured with or without EtOH for 72 h) and rat hepatocytes (control and EtOH-fed (Lieber-DeCarli diet). For recovery, EtOH was removed and replenished with control medium (48 hours for VA-13 cells) or control diet (10 days for rats). Results: EtOH-induced Golgi disassembly was associated with de-dimerization of the largest Golgi matrix protein giantin, along with impaired transport of selected hepatic proteins. After recovery from EtOH, Golgi regained their compact structure, and alterations in giantin and protein transport were restored.
The reports of dual-targeted proteins in plants have steadily increased over the past years. The vast majority of these proteins are soluble proteins distributed between compartments of the non-secretory pathway, predominantly chloroplasts and mitochondria. In contrast, dual-targeted transmembrane proteins, especially of the secretory pathway, are rare and the mechanisms leading to their differential targeting remain largely unknown. Here, we report dual-targeting of the Arabidopsis DUF679 Membrane Protein 1 (DMP1) to the tonoplast (TP) and the plasma membrane (PM). In Arabidopsis and tobacco two equally abundant DMP1 isoforms are synthesized by alternative translation initiation: a full length protein, DMP1.1, and a truncated one, DMP1.2, which lacks the N-terminal 19 amino acids including a TP-targeting dileucine motif. Accumulation of DMP1.1 and DMP1.2 in the TP and the PM, respectively, is Brefeldin A-sensitive, indicating transit via the Golgi. However, DMP1.2 interacts with DMP1.1, leading to
The Golgi complex, also known as the Golgi apparatus or simply the Golgi, is a cytoplasmic organelle. It is found in eukaryote cells, as in animals, plants, and fungi. The complex was discovered by Camillo Golgi in 1898. Golgi, who worked at Pavia, Italy, was ignored. His discovery was said to be dirt on his lenses. Years later, electron microscope pictures showed structures just like in the original Golgi drawings. It is made of several flattened sac-like membranes which look like a stack of pancakes. The main function of the Golgi apparatus is to process and package macromolecules, such as proteins and lipids. They come to the Golgi after being built, and before they go to their destination. In general, what the Golgi does is Much of the enzymatic processing is post-translational modification of proteins. The Golgi complex inspects them for flaws and discards extra material added during their manufacture, wraps them up and then targets them for packaging. The Golgi complex is especially active ...
Endogenous hHK3 localizes to the Golgi complex. The localization of endogenous Hook proteins in Hep2 cells (A, D, G, J, and M) was compared with the Golgi marke
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Reactome is pathway database which provides intuitive bioinformatics tools for the visualisation, interpretation and analysis of pathway knowledge.
Eukaryotic cells perform continuous recycling of the plasma membrane proteins and extracellular matrix molecules from the cell surface back to the cytoplasm (for plant cells, see Low and Chandra, 1994; Robinson et al., 1998). Our recent study (Baluška et al., 2002) provides experimental evidence that cell wall pectins are internalized after in muro de-esterification (Micheli, 2001) and cross-linking with calcium and boron (Matoh and Kobayashi, 1998;Kobayashi et al., 1999). These almost exclusive cell wall pectin epitopes, reactive to JIM5 and RGII antibodies, accumulate abundantly within intracellular BFA-induced compartments, which are obviously formed through aggregation of trans-Golgi networks and putative plant endosomes (Baluška et al., 2002). Here, we report that intracellular BFA compartments accumulate these cell wall pectins in meristematic cells of maize and wheat, but not of zucchini and alfalfa, root apices. Intriguingly, boron deprivation inhibits endocytosis of cell wall pectins. ...
XPLDHTNVTA PQASMMFQYF VKVVPTVYMK VDGEAPLPPQ VLRTNQFSVT RHEKVANGLL GDQGLPGVFV LYELSPMMVK LTEKHRSFTH FLTGVCAIIG GMFTVAGLID SLIYHSARAI QKKIDLGKTT ...
The mammalian Golgi complex is composed of stacks of flattened cisternae linked through tubules to form a contiguous juxtanuclear ribbon. The stacked cisternae reflect the compartmentalization of Golgi enzymes for the processing of transiting cargo (Mellman and Simons, 1992; Puthenveedu and Linstedt, 2005). Cargo movement through the stack has been variously suggested to occur in vesicles, in maturing cisternae, or by tubular connections between cisternae (Malhotra et al., 1989; Mollenhauer and Morre, 1991; Glick et al., 1997; Allan and Balch, 1999; Pelham and Rothman, 2000; Trucco et al., 2004). Although not exclusive of other processes, maturation has gained recent support (Emr et al., 2009). This model starts with the creation of cargo-containing cis-Golgi cisternae. The cargo stays within these cisternae and is sequentially processed when the cis enzymes are replaced with medial enzymes, which are subsequently replaced with trans enzymes. As cisternae progress through the Golgi stack, this ...
Supplementary MaterialsAdditional file 1: Table S1. group). Group (A & T), dual therapy with Adr (0.25?g/ml) and Tu (0.8?g/ml); Group (A), monotherapy with Adr (0.25?g/ml), and the control group. The colored dots represent over-expressed or under-expressed genes; the black dots represent unchanged genes. em P /em ? ?0.05. (PPTX 80 kb) 13046_2018_935_MOESM3_ESM.pptx (81K) GUID:?DD86D9AB-143A-41D8-8E65-23ABA4296B81 Additional file 4: Figure S3. Expression levels of CHOP, Cl-PARP and Cl-caspase 3 in SGC7901 detected by IF after treatment with monotherapy or dual therapy for 48?h. The concentrations of drugs were the same as those in Additional file 3: Physique S2. (400 ; scale bar, 50?m.) (PPTX 556 kb) 13046_2018_935_MOESM4_ESM.pptx (556K) GUID:?A2B89A2C-2E37-48C3-8062-7981706090A1 Additional file 5: Figure S4. Brefeldin A (BFA) can mimic the effects of Tu on MDR GC cells. a The effects of Tu on glycoproteins-L1CAM and TIMP1. GC cells were treated with Tu (0.8?g/ml) for 48?h before harvest. All ...
The Golgi apparatus is a packaging center Golgi apparatus or Golgi body or Golgi complex is a membrane-bound organelle, associated with the processing of…
We have studied changes in the Golgi morphology in Madin-Darby canine kidney cells as a result of chemically induced DNA damage, and how such morphological change affects synthesis and sorting of sulphated PGs in the cell line ...
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TY - JOUR. T1 - ADP ribosylation factor 6 regulates neuronal migration in the developing cerebral cortex through FIP3/arfophilin-1-dependent endosomal trafficking of N-cadherin. AU - Hara, Yoshinobu. AU - Fukaya, Masahiro. AU - Hayashi, Kanehiro. AU - Kawauchi, Takeshi. AU - Nakajima, Kazunori. AU - Sakagami, Hiroyuki. PY - 2016. Y1 - 2016. N2 - During neural development, endosomal trafficking controls cell shape and motility through the polarized transport of membrane proteins related to cellcell and cellextracellular matrix interactions. ADP ribosylation factor 6 (Arf6) is a critical small GTPase that regulates membrane trafficking between the plasma membrane and endosomes. We herein demonstrated that the knockdown of endogenous Arf6 in mouse cerebral cortices led to impaired neuronal migration in the intermediate zone and cytoplasmic retention of N-cadherin and syntaxin12 in migrating neurons. Rescue experiments with separation-of-function Arf6 mutants identified Rab11 familyinteracting ...
Transition zones are associated with the Golgi stacks. They are close to each other. This makes sense because the communication is more efficient. Vesicles dont need to travel long distances and the existence of the Golgi apparatus itself depends on a continuous process of vesicle incoming. It has been observed that a new transition zone led quickly to the nearby formation of a new Golgi stack. On the contrary, if a transition zone disappears, the associated Golgi cisternae are also lost. Transition zones can fuse with others and one transition zone can be split in two. Their associated Golgi stacks match this behavior. Vesicles budding from the transition zones are COPII coated vesicles ( COPII: coat protein II; Figure 1). Several proteins are involved in the formation of this COPII molecular framework: Sec16, Sar1 GTPases, Sec23/24 and Sec13/31. In this order, they are assembled at the cytosolic surface of the transition zone membranes. Transition zones are the more suitable environments for ...
Anti-Golgi complex antibodies (AGAs) are primarily associated with systemic lupus erythematosus and Sjögrens syndrome. Here we report on the immunoreactivity of AGAs against five Golgi autoantigens (giantin, golgin-245, golgin-160, golgin-95/GM130, and golgin-97) and provide data from epitope mapping on the most common Golgi autoantigen, namely giantin. A total of 80 human sera containing AGAs, as defined by indirect immunofluorescence on HEp-2 cells, were analyzed by ELISA using recombinant autoantigens and immunoprecipitation. The proportion of AGA sera that reacted with the five Golgi autoantigens was correlated with the molecular mass of the Golgi antigens. Autoantibodies to giantin, the largest Golgi autoantigen, were the predominant AGAs, being found in 50% of the AGA sera. Epitope mapping of giantin was performed using six recombinant fragments spanning the entire protein. Antigiantin-positive sera with low titer autoantibodies recognized epitopes in the carboxyl-terminal fragments that are
Constitutive Secretion: Advanced Look --, 2.) Exocytosis After leaving the Golgi apparatus, proteins following the constitutive secretion pathway merge with the cell membrane and release their cargo by a process called exocytosis. Clicking on each of the thumbnail images will bring up a larger, labeled version of the described scene.. To see the Flash movie for the following sequence of images, click here.. ...
Arl1 (ARF like protein1) is a poorly understood member of ARF family small GTPases. This thesis presents an original characterization of Arl1 and its effectors. Arl1 was localized to the tans Golgi under EM. Over expression of guanine nucleotide mutants of Arl1 dramatically affects the structure and function of Golgi apparatus. Arl1-GTP was found to interact with GRIP domain of Golgins (Golgin-97, Golgin-245, GCC1 and KIAA0336). The interaction was dependent on the conserved amino acids on both switch II region of Arl1 and the GRIP domain. Collectively, the research presented in this thesis reveals Arl1 is a new regulator of Golgi structure and function and one mechanism of Arl1a??s function is that it recruits and regulates its effectors a?? GRIP domain Golgins to Golgi ...
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COPⅠ囊泡:最初研究者利用三磷酸鳥苷(GTP)衍生物GTPγS(一種富含高爾基體膜的細胞質與抗水解的GTP衍生物)共培養時,發現高爾基體池之間存在一種囊泡轉運結構[9](後來在真核細胞中也證實此結構的存在[10])。除了脂質成分外,參與此囊泡形成的成份還有7種外被體蛋白(即外被體α、β、β′、γ、δ、ε、ζ)。這些外被體蛋白相互作用形成的復合物就是COPⅠ囊泡[11][12]。亞單位α、β′、ε在結構上與網格蛋白及COPⅡ囊泡的外層組分具有較高的一致性,形成復合物的內層組分稱為B亞復合物(主要負責與靶蛋白結合),而亞單位β、γ、δ、ζ 與網格蛋白及COPⅡ囊泡的內層組分相似,形成復合物的內層組分稱為F亞復合物,該亞復合物主要負責與靶蛋白結合,並且直接與COPⅠ囊泡形成的招募者ADP核糖基化因子(英语:ADP ribosylation factor)(ADP ribosylation ...
Phosphatidylinositol-4-phosphate-binding protein that links Golgi membranes to the cytoskeleton and may participate in the tensile force required for vesicle budding from the Golgi. Thereby, may play a role in Golgi membrane trafficking and could indirectly give its flattened shape to the Golgi apparatus. May also bind to the coatomer to regulate Golgi membrane trafficking. May play a role in anterograde transport from the Golgi to the plasma membrane and regulate secretion. Has also been involved in the control of the localization of Golgi enzymes through interaction with their cytoplasmic part. May play an indirect role in cell migration. Has also been involved in the modulation of mTOR signaling. May also be involved in the regulation of mitochondrial lipids biosynthesis (By similarity).
Figure 2. Flow cytometric characterization of γδ T cells in our patient demonstrates specific expansion of a homogeneous Vδ2+ T cell population. Flow cytometry performed on frozen PBMC either unstimulated for surface markers or PMA/ionomycin/brefeldin A stimulated for intracellular molecules. (A) FACS used to identify live, singlet lymphocytes (not shown), which were gated on to identify CD3+ T cells in the patient and a representative IFX-treated control (HC). CD3+ cells further gated on to identify Vδ1+/Vδ2+ T cells. The indicated plots display markers specific to the Vδ2+ T cell population with gates based on FMO control (not shown). (B) Mass cytometry used to identify live, singlet, CD3+CD14-CD19-TCRγδ+ cells in the patients PBMC for expression of the indicated markers. (C) viSNE analysis performed using 36 markers to cluster PBMC populations in the patient and 5 age-matched male patients with AS. CD3ε, CD4, CD8α, CD14, CD19, CD56, and TCRγδ antigens were used to gate indicated ...
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4423 Purpose: To study the mechanism by which an antibiotic brefeldin A (BFA) inhibits proliferation of androgen-responsive prostatic cancer LNCaP cells, focusing on cell cycle and androgen receptor (AR). Materials and Methods: Androgen-mediated cellular events in LNCaP cells were induced using 5α-dihydrotestosterone (DHT) as an androgenic mediator. Effect of BFA on DHT-stimulated cell growth was first assessed, and its regulatory mechanism(s) was further explored by examining cell cycle and AR activity/expression using flow cytometry, AR binding assay, and Western blot analysis. Results: DHT (1 nM) stimulated LNCaP cell growth by ∼37% above control; however, BFA (30 ng/ml) was capable of completely inhibiting such DHT-stimulated proliferation. Cell cycle analysis showed that this growth inhibition was associated with ∼75% reduction in the cell number in the S phase, indicating a blocking of G1-S phase transition. Such a G1 growth arrest was confirmed by a drastic (,80%) down-regulation of ...
Platelet-derived growth factor is a potent mitogen for cells of mesenchymal origin. It is made up of two polypeptide chains (A and B) combined in three disulfide-linked dimeric forms (AA, AB, and BB). Here, the biosynthesis and proteolytic processing of the two homodimeric forms of PDGF (AA and BB) were studied in CHO cells stably transfected with A-chain (short splice version) or B-chain cDNA. PDGF-AA was processed to a 30-kD molecule which was secreted from the cells. In contrast, PDGF-BB formed two structurally distinct end products; a minor secreted 30-kD form and a major cell-associated 24-kD form. Immunocytochemical studies at light- and electron-microscopical levels revealed presence of PDGF in the Golgi complex, in lysosomes, and to a smaller extent in the ER. From analysis of cells treated with brefeldin A, an inhibitor of ER to Golgi transport, it was concluded that dimerization occurs in the ER, whereas the proteolytic processing of PDGF-AA and PDGF-BB precursors normally occurs in a ...