贵州香猪IGF 1基因的克隆及组织分布

应用RT-PCR技术从香猪肝脏克隆到胰岛素样生长因子1(insulin-like growth factor 1,IGF-1)基因,共612bp,包含完整的开放读码框,与已知猪种的核苷酸相似性为99%~100%,编码的153个氨基酸包括信号肽、前体肽、B、C、A、D、E区,成熟肽仅由B到D区组成(70aa).香猪IGF-1的氨基酸序列与长白猪完全一样,与淞辽黑猪相差一个氨基酸(E区);与人、犬、牛、马等的差异主要集中在信号肽、前体肽和E区,成熟肽完全相同;与小鼠的差异最大,成熟肽区有4个氨基酸不同,其他区域还有11个氨基酸不同.对香猪IGF-1成熟肽的三维结构分析结果显示,蛋白有3个α-螺旋,3对二硫键分别联系α-螺旋的N端和C端.对香猪IGF-1基因的组织分布研究结果显示,IGF-1基因在肝脏、脾、脂肪、软骨、肌肉、子宫组织中均有表达,其中肝脏的表达量最高;脊髓、肺中未检测到表达,提示IGF-1的旁分泌作用具有组织特异性.     

Regulation by growth hormone of number of chondrocytes containing IGF-I in rat growth plate

Whether growth hormone stimulates longitudinal bone growth by a direct effect at the site of the growth plate or indirectly by increasing the concentration of circulating somatomedins (insulin-like growth factors) has been the subject of controversy. Immunohistochemical methods were used to explore the localization and distribution of insulin-like growth factor I (IGF-I) immunoreactivity in the epiphyseal growth plate of the proximal tibia of male rats. Cells in the proliferative zone of the growth plate of normal rats exhibited a bright immunofluorescence, whereas cells in the germinal and hypertrophic zones stained only weakly. In rats subjected to hypophysectomy, the number of fluorescent cells was markedly reduced. When the hypophysectomized rats were treated with growth hormone, either systemically or at the site of the growth plate, the number of IGF-I-immunoreactive cells in the proliferative zone was increased. The results show that IGF-I is produced in proliferative chondrocytes in the growth plate and that the number of IGF-I-containing cells is directly regulated by growth hormone. These findings suggest that IGF-I has a specific role in the clonal expansion of differentiated chondrocytes and exerts its function locally through autocrine or paracrine mechanisms.     

胰岛素样生长因子Ⅰ

胰岛素样生长因子 I(IGF-I)分子量约7000道尔顿,IGF-I 结合蛋白对 IGF-I具有保护和调节作用.卵泡颗粒细胞 IGF-I 的分泌受促性腺激素、雌二醇、卵泡大小、各种生长因子及颗粒细胞自身的调节.在卵泡,IGF-I 刺激卵泡颗粒细胞的代谢、增生、分化,甾体激素的生成及受体的诱导,并对膜-间质细胞具有旁分泌作用.     

Construction of a novel oncogene based on synthetic sequences encoding epidermal growth factor

The autocrine model postulates that constitutive release of a mitogenic growth factor can lead to uncontrolled proliferation and cell transformation. A synthetic polynucleotide encoding epidermal growth factor conferred a tumorigenic phenotype on cells. These cells were transformed through the action of an autocrine circuit having an extracellular component.     

Expression of a platelet-derived growth factor-like protein in simian sarcoma virus transformed cells

The near identity of the partial amino acid sequence of human platelet-derived growth factor (PDGF) and that predicted for p28sis, the putative transforming protein of the simian sarcoma virus (SSV), suggests expression of a growth factor activity may be central for transformation by SSV. It is now reported that SSV-transformed cells but not control cells contain a growth factor activity that is identical to PDGF in immunoassay, in mitogenic dose response, and in specific mitogenic activity. The protein immunoprecipitated by antiserum to human PDGF has an apparent molecular weight of 20,000, identical to that of p20sis, the putative intracellular degradation product of p28sis. The results support the concept that expression of a PDGF-like molecule, which appears to be the product of the viral-sis gene, is responsible for the abnormal regulation of growth is SSV-transformed cells.     

Fetal brain growth: selective action by growth hormone

Growth hormone was administered to pregnant rats maintained under dietary control, and fetal and placental growth and nutrition were examined. Growth hormone had a selective action on brain growth that could not be attributed to nutrient mobilization but suggested a trophic factor which is unique to the brain.     

拔毛·剃毛对绵羊皮肤中GHR·IGF-1·IGF-1R·KAP3.2和KAP6-1基因表达的影响

选取36只新疆细毛羊随机分成6组进行拔毛、剃毛处理,于第0、3、6、9、12、50天采集皮肤样品,用反转录多聚酶链式反应(RT-PCR)方法,定量分析绵羊皮肤中生长激素受体(GHR)、胰岛素样生长因子1(IGF-1)和胰岛素样生长因子1型受体(IGF-1R)、角蛋白关联蛋白KAP3.2和KAP6-1mRNA的相对丰度。实验结果显示,与对照组相比,剃毛可显著提高IGF-1的表达量,但对GHR、IGF-1R、KAP3.2和KAP6-1的表达量均无明显的影响;而拔毛对皮肤中GHRI、GF-1I、GF-1R、KAP3.2和KAP6-1基因表达均无明显影响。     

Inhibition of lipolytic action of growth hormone and glucocorticoid by ultraviolet and x-radiation

Addition of catecholamines or growth hormone plus glucocorticoid activates lipolysis in isolated white-fat cells of the rat. If the fat cells were irradiated just before the addition of growth hormone and glucocorticoid, their lipolytic action was abolished. However, irradiation did not affect the activation of lipolysis by catecholamines.     

Neuroleukin: a lymphokine product of lectin-stimulated T cells

Neuroleukin is a lymphokine product of lectin-stimulated T cells that induces immunoglobulin secretion by cultured human peripheral blood mononuclear cells. Neuroleukin acts early in the in vitro response that leads to formation of antibody-secreting cells, but continued production of immunoglobulin by differentiated antibody-secreting cells is neuroleukin-independent. Although the factor is not directly mitogenic, cellular proliferation is a late component of the response to neuroleukin. Neuroleukin does not have B-cell growth factor (BCGF) or B-cell differentiation factor (BCDF) activity in defined assays. Neuroleukin-evoked induction of immunoglobulin secretion is both monocyte- and T-cell-dependent.     

不同光色对马岗鹅生长发育的影响

为研究不同波长的光处理对肉鹅生长性能及相关激素的影响,以０日龄马岗鹅为研究对象,分别采用白色（对照）、４８０ｎｍ蓝色和６６０ｎｍ红色ＬＥＤ灯照明,在第７、３５和６３天记录鹅的体质量和体尺,并翅下采血检测血清中的相关激素水平．结果发现,在第６３天,蓝光处理鹅体质量显著低于红光组（Ｐ＜０.０５）;处理间体尺指标在整个试验期只有胸深差异极显著（Ｐ＜０.０１）,试验第７天的体斜长、第３５天的背宽和第６３天的胫围差异极显著（Ｐ＜０.０１）．红光组肾上腺素（Ａｄｒｅｎａｌｉｎｅ,ＡＤＲ）水平显著性低于其他两组,血清生长激素（Ｇｒｏｗｔｈ ｈｏｒｍｏｎｅ,ＧＨ）、胰岛素样生长因子１（Ｉｎｓｕｌｉｎ ｌｉｋｅ ｇｒｏｗｔｈ ｆａｃｔｏｒ １,ＩＧＦ-１）和三碘甲状腺原氨酸（Ｔｒｉｉｏｄｏｔｈｙｒｏｎｉｎｅ,Ｔ３）各处理间差异不显著性（Ｐ＞０.０５）．研究结果表明,鹅在不同时期对蓝光和红光的敏感性不同,与白光对比,在试验后期蓝光抑制鹅生长,红光促进鹅生长．     

IGF-Ⅰ对不同绵羊皮肤中5个毛囊相关生长因子基因表达的影响

【目的】为探讨外源性IGF-Ⅰ对绵羊皮肤中毛囊生长调控的影响。【方法】选取36只新疆细毛羊，随机分成6组。在每只绵羊的左、右两侧肩胛前部分别进行拔毛、剃毛处理。同时在左侧肩胛前部的拔毛、剃毛和正常区的交叉处注射0.5ml IGF-Ⅰ（10ng•ml-1），然后在第0、3、6、9、12、50天采取皮样。用RT-PCR方法，测定各皮肤中GHR、IGF-Ⅰ、IGF-ⅠR、KAP3.2和KAP6-1的mRNA相对丰度。【结果】（1）IGF-Ⅰ可以下调正常皮肤中GHR基因的表达，对IGF-Ⅰ、IGF-ⅠR的表达没有显著的影响，能显著提高KAP3.2和KAP6-1的转录水平；（2）IGF-Ⅰ在3 d内可降低拔毛皮肤中GHR的表达，6 d以上无明显影响；对剃毛皮肤中的GHR表达无显著影响。IGF-Ⅰ对拔毛皮肤中的IGF-Ⅰ和IGF-ⅠR的表达均无明显影响；对剃毛皮肤中IGF-Ⅰ的表达有明显的促进作用，但IGF-ⅠR的变化不明显。IGF-Ⅰ对拔毛皮肤和剃毛皮肤中的KAP3.2 和KAP6-1的表达都能显著提高，且表达模式也基本一致，KAP3.2的表达早于KAP6-1的表达。【结论】IGF-Ⅰ对绵羊皮肤中的GHR和IGF-ⅠR的表达均无显著影响，对KAP3.2和KAP6-1的表达能显著提高，但呈现出颠倒的特定时序性，这是否是外源性IGF-Ⅰ不能促进体内毛囊生长的原因所在，有待进一步研究。     

IGF-1调控RBM3表达抑制低温应激诱导牦牛卵丘细胞凋亡

【目的】探索动物机体遭受低温应激及细胞冷冻过程中胰岛素样生长因子1(insulin-like growth factor, IGF-1)与RNA结合基序蛋白3(RNA-binding motif protein 3, RBM3)之间的作用关系,及IGF-1参与哺乳动物细胞抑制低温损伤的机制。【方法】体外培养牦牛卵丘细胞,采用实时荧光定量 PCR(quantitative real-time PCR, qRT-PCR)、蛋白免疫印迹(Western blot, WB )和免疫荧光技术检测不同浓度（0、50、100、200 ng·mL ^-1）IGF-1和低温应激（30℃、25℃）对RBM3表达影响。卵丘细胞经最佳浓度IGF-1(100 ng·mL ^-1)和对照组(0 IGF-1)作用30 h后,低温（30℃、25℃）应激8 h,比较RBM3表达水平。评估在低温应激组、100 ng·mL ^-1 IGF-1处理组和100 ng·mL ^-1 IGF-1+RBM3抑制剂处理组,卵丘细胞25℃应激8 h后凋亡水平差异,并从基因和蛋白水平检测3组卵丘细胞中凋亡相关基因Bax和Bcl-2的表达水平。【结果】 (1) IGF-1作用卵丘细胞后RBM3基因和蛋白的表达水平显著上升 (P<0.05),其在100 ng·mL ^-1 IGF-1处理组最高,免疫荧光检测显示100和200 ng·mL ^-1 IGF-1处理组卵丘细胞胞核和细胞质均可检测到RBM3,而0和50 ng·mL ^-1处理组,RBM3仅定位在细胞质。(2) 卵丘细胞经受低温应激时,RBM3的表达水平显著增加,但其在30℃和25℃应激处理组差异不显著;100 ng·mL ^-1 IGF-1作用卵丘细胞30 h后,其再次接受25℃、8 h低温应激,卵丘细胞中RBM3的表达水平显著高于低温应激前未经IGF-1处理卵丘细胞中RBM3的表达水平,且该处理组卵丘细胞胞质和胞核均可检测到RBM3。(3) 25℃应激后,100 ng·mL ^-1 IGF-1处理组卵丘细胞的凋亡率为(15.94±2.03)%,显著低于其在未经IGF-1处理组和100 ng·mL ^-1 IGF-1+RBM3抑制剂处理组中卵丘细胞的凋亡率,两者分别为(25.86±1.09)%和(20.14±2.65)%,在100 ng·mL ^-1 IGF-1处理组Bcl-2的表达水平显著高于其余两个处理组(P<0.05),而Bax的表达水平显著低于其余两个处理组 (P<0.05)。【结论】RBM3参与牦牛卵丘细胞低温应激调控,IGF-1可调控其在低温应激中的表达水平,从而降低低温诱导的卵丘细胞凋亡。本研究为揭示IGF-1和RBM3参与动物机体或细胞免受低温损伤的分子机制提供了关键信息,为体细胞和生殖细胞冷冻技术的提高提供了理论依据。     

Thyroid hormone induction of an autocrine growth factor secreted by pituitary tumor cells

Thyroid hormones stimulate the rate of cell division by poorly understood mechanisms. The possibility that thyroid hormones increase cell growth by stimulating secretion of a growth factor was investigated. Thyroid hormones are nearly an absolute requirement for the division of GH4C1 rat pituitary tumor cells plated at low density. Conditioned media from cells grown with or without L-triiodothyronine (T3) were treated with an ion exchange resin to remove T3 and were tested for ability to stimulate the division of GH4C1 cells. Conditioned medium from T3-treated cells was as active as thyroid hormone at promoting GH4C1 cell growth but did not elicit other thyroid hormone responses, induction of growth hormone, and down-regulation of thyrotropin-releasing hormone receptors, as effectively as T3 did. A substance or substances associated with T3-induced growth stimulatory activity migrated at high molecular weight at neutral pH and was different from known growth-promoting hormones induced by T3. The results demonstrate that thyroid hormones stimulate the division of GH4C1 pituitary cells by stimulating the secretion of an autocrine growth factor.     

新生儿窒息后血浆IL-6、IGF-1水平的变化及其与脑损伤的关系

目的 :探讨外周血白细胞介素 6 (IL 6 )与胰岛素样生长因子 1(IGF 1)在新生儿窒息中的变化及其与脑损伤的关系。方法 :采用放射免疫法检测 5 0例窒息新生儿及 2 0例正常新生儿生后第 1、3、7天血清IL 6与IGF 1水平变化 ,并分析其与窒息后脑损伤的关系。结果 :窒息新生儿生后 3d内血清IL 6水平显著降低 ,与对照组比较差异有统计学意义 (P <0 .0 1) ,生后第 7天接近正常对照组水平 ,差异无统计学意义 (P >0 .0 5 ) ;而IGF 1生后 1周内均明显高于正常对照组水平 ,差异有统计学意义 (P <0 .0 1) ;头颅CT显示有脑损伤组IL 6明显低于CT正常组 ,IGF 1明显高于CT正常组 ,差异有统计学意义 (P均 <0 .0 5 ) ,IGF 1与IL 6呈明显负相关 (r= 0 .6 38,P <0 .0 1)。结论 :窒息新生儿外周血IL 6水平明显降低 ,IGF 1水平明显增高 ,它们可能参与了新生儿窒息后脑损伤的病理生理过程。     

胰岛素样生长因子(IGFs)及其在早期胚胎发育中的作用

胰岛素样生长因子(IGFs)在哺乳动物的生长发育过程中通过受体介导对生物体的生长起重要的调节作用。其在早期的胚胎发育过程中,对胚胎的生长发育十分重要。IGFs通过与IGFBPs家族蛋白的结合调节早期胚胎发育过程中的细胞凋亡。IGF-1可以增加体外培养的胚胎的囊胚发育率,并与其它基因协同作用调节胚胎细胞的凋亡,但其确切的抗凋亡的分子机理目前仍在研究中。     

日粮不同碘、硒水平对绒山羊绒生长相关激素及酶的影响

为探讨日粮添加不同水平的碘和硒对辽宁绒山羊非产绒期和产绒期血液中褪黑激素（MT）、催乳素（PRL）、类胰岛素生长因子（IGF—I）、生长激素（GH）、甲状腺过氧化物酶（TPO）以及脱碘酶（DIO）的影响,选择36只体况良好、体重相近（（38．0±2．94）kg）的2周岁辽宁绒山羊作为试验动物,采用2×3完全随机试验设计,随机分为6组。分别在基础日粮中添加3个水平的碘（0、2和4mg／kg,DM）和2个水平的硒（0和1mg／kg,DM）进行饲喂。试验结果表明：1）非产绒期,日粮添加碘显著提高了血液中GH和IGF1的浓度,降低了血浆MT的浓度（P〈0．05）,对PRL、TPO和D10浓度没有显著影响（P〉0．05）。添加硒对血液MT、PRL、GH、IGF—I和TPO没有影响,但是显著提高了DIO的浓度（P〈0．05）。2）产绒期,日粮添加碘极显著提高了血液中IGF-I的浓度（P〈0．01）,对MT、PRL、GH、TPO和DIO浓度没有影响。添加硒则显著提高了DIO的浓度（P〈0．05）,对血浆MT、PRL、GH、IGF—1和TP0没有影响。通过2个阶段的比较,综合碘促绒生长作用,推断碘或甲状腺激素促进山羊绒生长的机制可能是通过调控IGF—1分泌途径实现的;硒仅提高了血液中脱碘酶的浓度。     

A plant peptide encoded by CLV3 identified by in situ MALDI-TOF MS analysis

The Arabidopsis CLAVATA3 (CLV3) gene encodes a stem cell-specific protein presumed to be a precursor of a secreted peptide hormone. Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) applied to in situ Arabidopsis tissues determined the structure of a modified 12-amino acid peptide (MCLV3), which was derived from a conserved motif in the CLV3 sequence. Synthetic MCLV3 induced shoot and root meristem consumption as cells differentiated into other organs, displaying the typical phenotype of transgenic plants overexpressing CLV3. These results suggest that the functional peptide of CLV3 is MCLV3.     

A heparin-binding growth factor secreted by macrophage-like cells that is related to EGF.

Macrophage-like U-937 cells secrete a 22-kilodalton heparin-binding growth factor that is mitogenic for BALB-3T3 fibroblasts and smooth muscle cells, but not endothelial cells. The amino acid sequence predicted from complementary DNA clones indicates that the mitogen is a new member of the epidermal growth factor (EGF) family. This heparin-binding EGF-like growth factor (HB-EGF) binds to EGF receptors on A-431 epidermoid carcinoma cells and smooth muscle cells, but is a far more potent mitogen for smooth muscle cells than is EGF. HB-EGF is also expressed in cultured human macrophages and may be involved in macrophage-mediated cellular proliferation.     

湖羊GHR和IGF-Ⅰ基因表达的发育性变化 及其与肉质性状的关联

 【目的】探讨生长激素受体（growth hormone receptor,GHR）和胰岛素样生长因子-Ⅰ（insulin-like growth factor-Ⅰ,IGF-Ⅰ）基因在湖羊不同生长阶段背最长肌中表达丰度与肉质性能的相关性以及这两个基因表达水平的关联性,为湖羊肌肉生长性状的选育提供遗传学资料。【方法】利用荧光定量RT-PCR分析GHR和IGF-Ⅰ基因在湖羊早期生长背最长肌肉组织中的mRNA的发育性变化。【结果】①出生后随着月龄的增加,母羊GHR基因在背最长肌的表达趋势为：先升高后降低再升高再降低最后再升高,最后6月龄到达最高点;公羊GHR在背最长肌的表达趋势为：先升高到2月龄到达一个峰值,2月龄到4月龄为一个降低的过程,4月龄到6月龄又升高,并到达最高点;母羊IGF-Ⅰ基因在背最长肌的表达趋势为：由2日龄开始依次升高最后于6月龄到达最高点;公羊IGF-Ⅰ基因在背最长肌的表达趋势为：先升高到1月龄到达一个峰值,1月龄到3月龄为一个降低的过程,并于3月龄降至与初生接近相等的水平,此后随月龄增加逐渐升高,并于6月龄到达最高点;②GHR和IGF-Ⅰ基因在湖羊各月龄间大多存在显著或极显著差异,湖羊的公羊和母羊的GHR和IGF-Ⅰ基因的相同生长阶段的表达也大多存在显著或极显著差异;③GHR和IGF-Ⅰ基因的表达存在显著正相关（0.01＜P＜0.05）,GHRI和GF-I基因与肌纤维直径均存在极显著正相关（P＜0.01）,GHR与肌纤剪切力存在极显著正相关（P＜0.01）,IGF-Ⅰ与肌纤剪切力存在显著正相关（0.01＜P＜0.05）,GHR和IGF-Ⅰ基因与肌纤维密度均存在极显著负相关（P＜0.01）。【结论】性别和年龄对于GHR和IGF-Ⅰ基因在湖羊不同生长阶段的肌肉中的表达具有重要影响;出生后,各基因表达水平并非随之上升或者下降,各基因表达水平出现拐点的时间并不相同;GHR和IGF-Ⅰ基因在湖羊早期肌肉性状的表达为显著正相关,可以作为湖羊早期肉质性状的候选基因。     

鸡卵泡颗粒细胞转染Bcl-2基因对IGF-1分泌的影响

选用正在产蛋的罗曼鸡,取体积排序第一（F1）和第四（F4）的卵泡,分离颗粒细胞层细胞。采用脂质体介导方法将来源于F1和F4卵泡的颗粒细胞用PBS（对照）、空载体或Bcl-2重组质粒处理,然后在不完全无血清培养基（不添加胰岛素）中培养48和96h,用流式细胞术检测Bcl-2蛋白表达,用放射免疫测定技术检测IGF-1的含量。结果发现,转染Bcl-2重组质粒组的Bcl-2蛋白表达量和IGF-1分泌量均多于其他各组。分析来源于不同卵泡期卵泡颗粒细胞的分泌功能,发现随时间的增加F1细胞IGF-1分泌量减少,而F4的IGF-1分泌量基本不变。结果表明,在鸡卵泡颗粒细胞中转染的Bcl-2基因具有表达功能,表达的蛋白具有调节鸡卵泡颗粒细胞分泌IGF-1的作用;鸡卵泡颗粒细胞IGF-1的分泌还受鸡卵泡的大小和颗粒细胞在体外培养时间的影响。