共查询到20条相似文献,搜索用时 73 毫秒
1.
France Demaugre Yannick Philippe Sokavuth Sar Bernard Pileire Laurence Christa Chantal Lasserre Christian Brechot 《European journal of biochemistry》2004,271(19):3812-3820
HIP/PAP is a C-type lectin overexpressed in hepatocellular carcinoma (HCC). Pleiotropic biological activities have been ascribed to this protein, but little is known about the function of HIP/PAP in the liver. In this study, therefore, we searched for proteins interacting with HIP/PAP by screening a HCC cDNA expression library. We have identified the RII alpha regulatory subunit of cAMP-dependent protein kinase (PKA) as a partner of HIP/PAP. HIP/PAP and RII alpha were coimmunoprecipitated in HIP/PAP expressing cells. The biological relevance of the interaction between these proteins was established by demonstrating, using fractionation methods, that they are located in a same subcellular compartment. Indeed, though HIP/PAP is a protein secreted via the Golgi apparatus we showed that a fraction of HIP/PAP escaped the secretory apparatus and was recovered in the cytosol. Basal PKA activity was increased in HIP/PAP expressing cells, suggesting that HIP/PAP may alter PKA signalling. Indeed, we showed, using a thymidine kinase-luciferase reporter plasmid in which a cAMP responsive element was inserted upstream of the thymidine kinase promoter, that luciferase activity was enhanced in HIP/PAP expressing cells. Thus our findings suggest a novel mechanism for the biological activity of the HIP/PAP lectin. 相似文献
2.
Xiaoyan Zheng Qian Li Hong Tian Hanchao Li Yifei Lv Yanhua Wang Lan He Yongwei Huo Zhiming Hao 《Journal of cellular and molecular medicine》2020,24(12):6804-6821
Hepatocarcinoma‐intestine‐pancreas/pancreatitis‐associated protein (HIP/PAP), a C‐type lectin, exerts anti‐oxidative, anti‐inflammatory, bactericidal, anti‐apoptotic, and mitogenic functions in several cell types and tissues. In this study, we explored the role of HIP/PAP in pulmonary fibrosis (PF). Expression of HIP/PAP and its murine counterpart, Reg3B, was markedly increased in fibrotic human and mouse lung tissues. Adenovirus‐mediated HIP/PAP expression markedly alleviated bleomycin (BLM)‐induced lung injury, inflammation, and fibrosis in mice. Adenovirus‐mediated HIP/PAP expression alleviated oxidative injury and lessened the decrease in pulmonary superoxide dismutase (SOD) activity in BLM‐treated mice, increased pulmonary SOD expression in normal mice, and HIP/PAP upregulated SOD expression in cultured human alveolar epithelial cells (A549) and human lung fibroblasts (HLF‐1). Moreover, in vitro experiments showed that HIP/PAP suppressed the growth of HLF‐1 and ameliorated the H2O2‐induced apoptosis of human alveolar epithelial cells (A549 and HPAEpiC) and human pulmonary microvascular endothelial cells (HPMVEC). In HLF‐1, A549, HPAEpiC, and HPMVEC cells, HIP/PAP did not affect the basal levels, but alleviated the TGF‐β1‐induced down‐regulation of the epithelial/endothelial markers E‐cadherin and vE‐cadherin and the over‐expression of mesenchymal markers, such as α‐SMA and vimentin. In conclusion, HIP/PAP was found to serve as a potent protective factor in lung injury, inflammation, and fibrosis by attenuating oxidative injury, promoting the regeneration of alveolar epithelial cells, and antagonizing the pro‐fibrotic actions of the TGF‐β1/Smad signaling pathway. 相似文献
3.
Short-term administration of the glucose analog 5-thio-
-glucose to primiparous lactating rats reduced mammary tissue lactose concentrations to half of control levels. Treatment with colchicine alone caused slight reductions in mammary tissue lactose content. These treatments did not alter the morphology or degree of development of rough endoplasmic reticulum or Golgi apparatus, but did cause alterations in secretory vesicles. In mammary tissue from untreated lactating animals, large, swollen secretory vesicles were abundant in apical regions of epithelial cells. After thioglucose administration secretory vesicles in the apical cytoplasm were smaller and were more densely packed with contents. While administration of colchicine alone caused accumulation of large numbers of nearly fully swollen vesicles, treatment with both colchicine and thioglucose induced accumulation of smaller, less fully developed secretory vesicles which contained morphologically recognizable casein micelles. Mammary tissue from late gestation rats was low in lactose; vesicles in this tissue resembled secretory vesicles in tissue from rats treated with thioglucose in that they were small and densely packed. These observations suggest that lactose, an osmoregulator in mammary gland, is transferred from Golgi apparatus to the apical cell surface within secretory vesicles. Lactose appears to be important for secretory vesicle maturation in mammary epithelial cells. 相似文献
4.
R. A. Tedman 《Journal of Zoology》1983,200(1):131-141
Ultrastructural observations were made of the non-lactating and lactating mammary gland of the Weddell seal, and measurements of several cell components were compared with those in other species to determine whether there are any morphological modifications within the gland to explain the unusual milk composition and very rapid growth of sucking young in this species.
The mammary parenchyma in non-lactating and lactating Weddell seals is almost identical morphologically to that found in other mammals. Although the relative volumes of most organelles are similar to those in other eutherians, the relative volume of rough endoplasmic reticulum (RER) is reduced in the Weddell seal. In addition, the absolute and relative volumes of Golgi vacuoles are smaller in the Weddell seal, probably associated with the low lactose and water content of the milk. The synthesis and secretion of milkspecific proteins and fat droplets by mammary secretory cells in the Weddell seal appear to be identical to other eutherians. Relatively small numbers of fat droplets less than 1 μm diameter are present in epithelial cells, alveolar lumina and milk samples, and there is a far greater contribution by large fat droplets to the total fat volume of Weddell seal milk than milk from other mammals. 相似文献
The mammary parenchyma in non-lactating and lactating Weddell seals is almost identical morphologically to that found in other mammals. Although the relative volumes of most organelles are similar to those in other eutherians, the relative volume of rough endoplasmic reticulum (RER) is reduced in the Weddell seal. In addition, the absolute and relative volumes of Golgi vacuoles are smaller in the Weddell seal, probably associated with the low lactose and water content of the milk. The synthesis and secretion of milkspecific proteins and fat droplets by mammary secretory cells in the Weddell seal appear to be identical to other eutherians. Relatively small numbers of fat droplets less than 1 μm diameter are present in epithelial cells, alveolar lumina and milk samples, and there is a far greater contribution by large fat droplets to the total fat volume of Weddell seal milk than milk from other mammals. 相似文献
5.
We describe the generation of transgenic mouse lines expressing Cre recombinase in epithelial cells of the lactating mammary gland. As an expression vector, we used a P1-derived bacterial artificial chromosome (PAC) which harbors the gene for the secretory milk protein, whey acidic protein (Wap). Using homologous recombination in E. coli, the PAC was modified to carry the improved coding sequence of Cre recombinase (iCre). Transgenic lines carrying the WAPiCre PAC express Cre recombinase efficiently in the majority of mammary epithelial cells upon lactation. Of only four transgenic lines produced, three express Cre recombinase to a high efficiency. LoxP-flanked DNA sequences are recombined in virtually all epithelial cells of WAPiCre transgenic mice at lactation day 3. 相似文献
6.
Null mutation in the gene encoding plasma membrane Ca2+-ATPase isoform 2 impairs calcium transport into milk 总被引:2,自引:0,他引:2
Reinhardt TA Lippolis JD Shull GE Horst RL 《The Journal of biological chemistry》2004,279(41):42369-42373
The means by which calcium is transported into the milk produced by mammary glands is a poorly understood process. One hypothesis is that it occurs during exocytosis of secretory products via the Golgi pathway, consistent with the observation that the SPCA1 Ca2+-ATPase, which is expressed in the Golgi, is induced in lactating mammary tissue. However, massive up-regulation of the PMCA2bw plasma membrane Ca2+-ATPase also occurs during lactation and is more strongly correlated with increases in milk calcium, suggesting that calcium may be secreted directly via this pump. To examine the physiological role of PMCA2bw in lactation we compared lactating PMCA2-null mice to heterozygous and wild-type mice. Relative expression levels of individual milk proteins were unaffected by genotype. However, milk from PMCA2-null mice had 60% less calcium than milk from heterozygous and wild-type mice, the total milk protein concentration was lower, and an indirect measure of milk production (litter weights) suggested that the PMCA2-null mice produce significantly less milk. In contrast, lactose was higher in milk from PMCA2-null mice during early lactation, but by day 12 of lactation there were no differences in milk lactose between the three genotypes. These data demonstrate that the activity of PMCA2bw is required for secretion of much of the calcium in milk. This major secretory function represents a novel biological role for the plasma membrane Ca2+-ATPases, which are generally regarded as premier regulators of intracellular Ca2+. 相似文献
7.
Shennan DB 《Cellular & molecular biology letters》2008,13(4):514-525
The secretion of calcium into milk by mammary epithelial cells is a fundamentally important process. Despite this, the mechanisms
which underlie the movement of calcium across the lactating mammary gland are still poorly understood. There are, however,
two models which describe the handling of calcium by mammary epithelial cells. On the one hand, a model which has existed
for several decades, suggests that the vast majority of calcium enters milk via the Golgi secretory vesicle route. On the
other hand, a new model has recently been proposed which implies that the active transport of calcium across the apical membrane
of mammary secretory cells is central to milk calcium secretion. This short review examines the strengths and weaknesses of
both models and suggests some experiments which could add to our understanding of mammary calcium transport. 相似文献
8.
Timothy A. Reinhardt John D. LippolisRandy E. Sacco 《Biochemical and biophysical research communications》2014
Plasma membrane Ca2+-ATPase 2 (PMCA2) knockout mice showed that ∼60% of calcium in milk is transported across the mammary cells apical membrane by PMCA2. The remaining milk calcium is thought to arrive via the secretory pathway through the actions of secretory pathway Ca2+-ATPase’s 1 and/or 2 (SPCA1 and 2). However, another secretory pathway calcium transporter was recently described. The question becomes whether this Golgi Ca2+/H+ antiporter (TMEM165) is expressed sufficiently in the Golgi of lactating mammary tissue to be a relevant contributor to secretory pathway mammary calcium transport. TMEM165 shows marked expression on day one of lactation when compared to timepoints prepartum. At peak lactation TMEM165 expression was 25 times greater than that of early pregnancy. Forced cessation of lactation resulted in a rapid ∼50% decline in TMEM165 expression at 24 h of involution and TMEM165 expression declined 95% at 96 h involution. It is clear that the timing, magnitude of TMEM165 expression and its Golgi location supports a role for this Golgi Ca2+/H+ antiporter as a contributor to mammary Golgi calcium transport needs, in addition to the better-characterized roles of SPCA1&2. 相似文献
9.
10.
T W Keenan M Sasaki W N Eigel D J Mooré W W Franke I M Zulak A A Bushway 《Experimental cell research》1979,124(1):47-61
Fractions enriched in secretory vesicles were obtained from lactating bovine mammary tissue by a straightforward procedure involving gentle homogenization and centrifugation in isotonic milk salt solution containing Ficoll. Secretory vesicle-rich fractions could also be obtained from lactating rat mammary gland by this procedure. With rats, yields of vesicles were substantially increased by administration of colchicine or thioglucose to animals several hours before sacrifice. Isolated fractions were enriched in lactose and consisted predominantly of 0.2–1.2 μm diameter vesicles, many of which contained casein micelles. Enzymatic, compositional and morphological examination revealed vesicle preparations to be largely free of contamination by rough endoplasmic reticulum, mitochondria, nuclei, peroxisomes and lysosomes. Specific activity of several marker enzymes of the secretory vesicle fraction were similar to, or intermediate between, Golgi apparatus and milk lipid globule membranes. Amounts of cholesterol and gangliosides in vesicle fractions approached levels found in plasma membranes. In distribution of major phospholipids, secretory vesicles were intermediate between Golgi apparatus and milk lipid globule membranes. The pattern of polypeptides of secretory vesicle membrane was qualitatively similar to that of Golgi apparatus membranes. While there were similarities between these polypeptide patterns and that of lipid globule membranes, the latter contained relatively more of certain polypeptides, particularly the internal coat-associated polypeptides of the globule membrane. These observations are discussed in relation to the endomembrane hypothesis and the origin of the membrane of milk lipid globules. 相似文献
11.
Kozakai T Sakate M Masuo Y Uchide T Saida K 《Biochemical and biophysical research communications》2002,297(5):1339-1343
In an attempt to understand the roles of endothelin-1 (ET-1) and vasoactive intestinal contractor/endothelin-2 (VIC/ET-2), we have studied the genes for both peptides to be expressed in the mammary gland of lactating mice. We observed through real-time PCR analysis that ET-1 and VIC/ET-2 gene expression gradually increase after parturition and that ET-1 gene expression is significantly higher than that of VIC/ET-2. The distribution of ET-1 peptide was found to be localized mainly in the epithelial cells of the mammary gland at 14th day of lactation. ET-1 gene expression increases significantly, parallel to the increase in beta-casein gene expression, in epithelial cell lines (HC11) of mouse mammary gland after hormonal stimulation by addition of dexamethazone and prolactin. The observed increase in ET-1 expression in differentiated epithelial cells suggests physiological roles for ET-1, including milk production and secretion in the mammary gland of lactating mice. 相似文献
12.
Marcelo G. Cerdn Juan I. Young Esilda Zino Toms L. Falzone Vernica Otero Hctor N. Torres Marcelo Rubinstein 《Molecular reproduction and development》1998,49(3):236-245
The spatial, temporal, and hormonal pattern of expression of the β-casein gene is highly regulated and confined to the epithelial cells of the lactating mammary gland. Previous studies have shown that 1.7 kb of the bovine β-casein promoter were able to drive cell-specific and hormone-dependent expression to a mouse mammary cell line but failed to induce accurate expression to the mammary gland of transgenic mice. We investigated here the ability of 3.8 kb of the bovine β-casein gene promoter to drive the expression of the human growth hormone (hGH) gene in transgenic mice. A Northern blot analysis using total RNA obtained from different tissues of lactating and nonlactating females revealed the presence of hGH mRNA only in the mammary gland of lactating females. hGH mRNA was not detectable in the mammary gland of virgin females or males. A developmental analysis showed that hGH mRNA only peaked on parturition, resembling more closely the bovine β-casein temporal expression pattern rather than the murine. In situ hibridization studies performed on mammary gland sections showed that the cellular pattern of hGH expression was homogeneous in all lobules from heterozygous and homozygous transgenic mice. Silver grain counts on the tissue sections highly correlated with the hGH contents in the milk determined by radioimmunoassay (r = 0.996). Thus 3.8 kb of the bovine β-casein promoter direct a high-level expression of a reporter gene to the lactating mammary gland of transgenic mice in a tissue-specific and developmentally regulated manner. Mol. Reprod. Dev. 49:236–245, 1998. © 1998 Wiley-Liss, Inc. 相似文献
13.
14.
Sooyeon Lee Stephen R. Hennigar Samina Alam Keigo Nishida Shannon L. Kelleher 《The Journal of biological chemistry》2015,290(21):13064-13078
The zinc transporter ZnT2 (SLC30A2) imports zinc into vesicles in secreting mammary epithelial cells (MECs) and is critical for zinc efflux into milk during lactation. Recent studies show that ZnT2 also imports zinc into mitochondria and is expressed in the non-lactating mammary gland and non-secreting MECs, highlighting the importance of ZnT2 in general mammary gland biology. In this study we used nulliparous and lactating ZnT2-null mice and characterized the consequences on mammary gland development, function during lactation, and milk composition. We found that ZnT2 was primarily expressed in MECs and to a limited extent in macrophages in the nulliparous mammary gland and loss of ZnT2 impaired mammary expansion during development. Secondly, we found that lactating ZnT2-null mice had substantial defects in mammary gland architecture and MEC function during secretion, including fewer, condensed and disorganized alveoli, impaired Stat5 activation, and unpolarized MECs. Loss of ZnT2 led to reduced milk volume and milk containing less protein, fat, and lactose compared with wild-type littermates, implicating ZnT2 in the regulation of mammary differentiation and optimal milk production during lactation. Together, these results demonstrate that ZnT2-mediated zinc transport is critical for mammary gland function, suggesting that defects in ZnT2 not only reduce milk zinc concentration but may compromise breast health and increase the risk for lactation insufficiency in lactating women. 相似文献
15.
This study was aimed at establishing a new platform for real-time monitoring of milk-protein gene expression in the mammary glands. A transgenic reporter composed of the beta-lactoglobulin (BLG)/luciferase hybrid gene was targeted to the mammary glands of pregnant and lactating mice and luciferase activity was imaged in vivo with a low-light imaging system. The mammary glands of a 17-day pregnant mouse occupied an area comparable to that of a 6-day lactating mouse. Nevertheless, the intensity of the luciferase signal was much weaker and confined to regions in the inguinal and thoracic glands. A few small and defined locations of higher expression were also detected, indicating diversity in the initiation of this transgenic milk protein expression. In the lactating mice, high inter- and intra-heterogeneity among regions in a particular gland and among glands was demonstrated, and confirmed by ex vivo analysis of luciferase activity in mammary biopsies. The lack of correlation between luciferase activities and levels of beta-casein accumulation in these biopsies resulted, most probably, from the longer half-life of the native milk protein, compared to the activity of the transgenic marker in the tissue. Unilateral sealing of mammary glands for 4 hr resulted in complete abrogation of luciferase activity, establishing the BLG/luciferase transgene as a reliable tool to follow short-term stimuli. Dispersed mammary epithelial cells preserved luciferase activity in culture, and thus could be used for following mammary gland development after re-implantation. The bioluminescence-based methodology presented here eliminates averaging of heterogeneity in gene expression among glands, and misinterpretations resulting from sampling biopsies taken from inactive regions. Imaging luciferase expression in the mammary glands may enable an accurate monitoring of milk-protein gene expression during cyclic periods of development and apoptosis in a limited number of animals, and could be applied for reporting the consequences of selected drugs on milk-protein gene expression. 相似文献
16.
K U Wagner R J Wall L St-Onge P Gruss A Wynshaw-Boris L Garrett M Li P A Furth L Hennighausen 《Nucleic acids research》1997,25(21):4323-4330
To delete genes specifically from mammary tissue using the Cre-lox system, we have established transgenic mice expressing Cre recombinase under control of the WAP gene promoter and the MMTV LTR. Cre activity in these mice was evaluated by three criteria. First, the tissue distribution of Cre mRNA was analyzed. Second, an adenovirus carrying a reporter gene was used to determine expression at the level of single cells. Third, tissue specificity of Cre activity was determined in a mouse strain carrying a reporter gene. In adult MMTV-Cre mice expression of the transgene was confined to striated ductal cells of the salivary gland and mammary epithelial cells in virgin and lactating mice. Expression of WAP-Cre was only detected in alveolar epithelial cells of mammary tissue during lactation. Analysis of transgenic mice carrying both the MMTV-Cre and the reporter transgenes revealed recombination in every tissue. In contrast, recombination mediated by Cre under control of the WAP gene promoter was largely restricted to the mammary gland but occasionally observed in the brain. These results show that transgenic mice with WAP-Cre but not MMTV-Cre can be used as a powerful tool to study gene function in development and tumorigenesis in the mammary gland. 相似文献
17.
18.
Stephen C. Nickerson R. Michael Akers Bernard T. Weinland 《Cell and tissue research》1982,223(2):421-430
Summary Ultrastructural examination of milk secretory cells from lactating bovine mammary gland revealed presence of numerous microtubules in the apical and paranuclear cytoplasm, particularly in the vicinity of Golgi components. Most microtubules were oriented perpendicular to the apical plasma membrane and appeared to form a framework around Golgi dictyosomal elements and secretory vesicles. In comparison, non-secretory cells obtained from involuting glands displayed few microtubules and these were randomly located throughout the cytoplasm with no particular orientation. 相似文献
19.
Asymmetrical microtubule capping structures in frog palate cilia 总被引:3,自引:0,他引:3
The three-dimensional ultrastructure of the Golgi apparatus in milk secreting epithelial cells of bovine mammary gland was explored. From computer-aided reconstructions of serial thin sections, it was determined that the Golgi apparatus was composed of a single set of stacked cisternae. The three-dimensional shape of the dictyosome varied from cell to cell, but the overall shape was that of a hollow cone, cylinder, or bowl. The cis and trans surfaces of the dictyosome were arranged in three-dimensional space such that the cis face was located on the outer surface of the hollow structure and the trans face on the inner surface. The cytoplasmic channel (secretory channel) that traversed the longitudinal axis of the hollow dictyosome contained secretory vesicles. Densely stacked cisternae of rough endoplasmic reticulum surrounded the dictyosome, and microvesicles appeared to fuse with, or bud from, cisternae of both organelles. These findings suggest that Golgi apparatus of the lactating epithelial cell is highly organized and that the Golgi apparatus and secretory channel are essentially an independent compartment within the cell. 相似文献