Direct somatic embryogenesis and related gene expression networks in leaf explants of Hippeastrum ‘Bangkok Rose’

Hippeastrum, a highly diverse genus in the Amaryllidaceae family, is a valuable ornamental bulbous flowering plant. Somatic embryogenesis(SE) is an efficient method for mass production of Hippeastrum plantlets. Previous studies have been devoted to the in vitro propagation of Hippeastrum, but the SE and its regulatory networks are rarely reported. In this study, we established a direct SE method of Hippeastrum Bangkok Rose' using leaf bases as explants. MS supplemented with 1.00 mg·L^(-1)NAA +1.00 mg·L^(-1)KT + 0.25 mg·L^(-1)TDZ was the optimal medium for SE. Histological observations showed that the bipolar somatic embryo originated from the epidermal cell layer and underwent initiation,globular, scutellar and coleoptile stages. During SE, endogenous hormones of IAA, CTK, ABA, and SA were highly accumulated. Transcriptomic analysis revealed the genes encoding auxin biosynthesis/metabolic enzymes and efflux carriers were induced, while the auxin receptor of TIR1 and ARF transcriptional repressor of Aux/IAA were down-regulated and up-regulated, respectively, leading to suppression of auxin signaling. In contrast, cytokine signaling was promoted at the early stage of SE, as biosynthesis, transport, and signaling components were up-regulated.Various stress-related genes were up-regulated at the early or late stages of SE. Chromatin remodeling could also be dynamically regulated via distinct expression enzymes that control histone methylation and acetylation during SE. Moreover, key SE regulators, including WOXs and SERKs were highly expressed along with SE. Overall, the present study provides insights into the SE regulatory mechanisms of the Hippeastrum.

Effects of hypoxia,hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 in hepatic stellate cells

AIM: To study the effects of hypoxia, hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 (MMP-2) in hepatic stellate cells (HSC). METHODS: The expressions of MMP-2, tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) and membrane type matrix metalloproteinase-1 (MT1-MMP) in cultured rat HSC were detected by immunocytochemistry (ICC) and in situ hybridization (ISH). The contents of MMP-2 and TIMP-2 in culture supernatant were detected with ELISA and the activity of MMP-2 in supernatant was revealed by zymography. RESULTS: In the situation of hypoxia for 12h, the expression of MMP-2 protein was enhanced (hypoxia group positive indexes: 5.7 +/- 2.0, n=10; control: 3.2 +/- 1.0, n = 7; P【0.05), while TIMP-2 protein was decreased in HSC (hypoxia group positive indexes: 2.5 +/- 0.7, n = 10; control: 3.6 +/- 1.0, n = 7; P 【 0.05), and the activity (total A) of MMP-2 in supernatant declined obviously (hypoxia group: 7.334 +/- 1.922, n = 9; control: 17.277 +/- 7.424, n = 11; P 【 0.01). Compared the varied duration of hypoxia, the changes of expressions including mRNA and protein level as well as activity of MMP-2 were most notable in 6h group. The highest value(A(hypoxia)-A(control)) of the protein and the most intense signal of mRNA were in the period of hypoxia for 6h, along with the lowest activity of MMP-2. In the situation of hyperoxia for 12h, the contents (A(450)) of MMP-2 and TIMP-2 in supernatant were both higher than those in the control, especially the TIMP-2 (hyperoxia group: 0.0499 +/- 0.0144, n = 16; control: 0.0219 +/- 0.0098, n = 14; P 【 0.01), and so was the activity of MMP-2 (hyperoxia group: 5.252 +/- 0.771, n = 14; control: 4.304 +/- 1.083, n = 12; P 【 0.05), and the expression of MT1-MMP was increased. CONCLUSION: HSC is sensitive to the oxygen, hypoxia enhances the expression of MMP-2 and the effect is more marked at the early stage; hyperoxia mainly raises the activity of MMP-2.

Differential expression of a novel colorectal cancer differentiation-related gene in colorectal cancer

AIM: To investigate SBA2 expression in CRC cell lines and surgical specimens of CRC and autologous healthy mucosa. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used for relative quantification of SBA2 mRNA levels in 4 human CRC cell lines with different grades of differentiation and 30 clinical samples. Normalization of the results was achieved by simultaneous amplification of beta-actin as an internal control. RESULTS: In the exponential range of amplification, fairly good linearity demonstrated identical amplification efficiency for SBA2 and beta-actin (82%). Markedly lower levels of SBA2 mRNA were detectable in tumors, as compared with the coupled normal counterparts P【0.01). SBA2 expression was significantly (0.01】P 【 0.05) correlated with the grade of differentiation in CRC, with relatively higher levels in well-differentiated samples and lower in poorly-differentiated cases. Of the 9 cases with lymph nodes affected, 78% (7/9) had reduced SBA2 mRNA expression in contrast to 24% (5/21) in non-metastasis samples 0.01】P【0.05). CONCLUSION: SBA2 gene might be a promising novel biomarker of cell differentiation in colorectal cancer and its biological features need further studies.

Expression of vascular endothelial growth factor and its role in oncogenesis of human gastric carcinoma

AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF(165) complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or down-regulated. RESULTS: VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR, localized in both the cytoplasm and membrane. Introduction of VEGF(165) antisense into human gastric cancer cells (SGC-7901, immunofluorescence intensity, 31.6%)) resulted in a significant reduction in VEGF-specific messenger RNA and total and cell surface VEGF protein (immunofluorescence intensity, 8.9%) (P【0.05). Conversely, stable integration of VEGF(165) in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity, 75.4%) (P【0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tumor volume: 345.40 +/- 136.31 mm3)(P【0.05 vs control SGC-7901 group: 1534.40 +/- 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tumor volume: 2350.50 +/- 637.70 mm3) (P【0.05 vs control SGC-7901 group). CONCLUSION: This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.

Effect of 5-Aza-2'-deoxycytidine on the P16 tumor suppressor gene in hepatocellular carcinoma cell line HepG2

INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecular mechanisms of hepatocarcinogenesisremain poorly understood, an increasing number ofgenetic abnormalities have been recognized[7-10],for example, the p16 gene[11,12] the p53gene[13-18], the E-cadherin gene[19], and the c-mycgene[20].

Relationship between Fas/ FasL expression and apoptosis of colon adenocarcinoma cell lines

INTRODUCTIONFas/ FasL system has been identified as a keymediator of apoptosis in tumor cells[1-4]. Theoccurrence and development of neoplasm are closelyrelated to apoptosis[5-7] Most chemotherapeuticdrugs kill cancer cells mainly by inducingapoptosis[8-14].'

Identification of differentially expressed genes in human uterine leiomyomas using differential display

In searching of differentially expressed genes in human uterine leiomyomas, differential display was used with twelve pairs of primers to compare human uterine leiomyomas with matched myometrium. False positives were eliminated by reverse Northern analysis. Positives were confirmed by Northern blot analysis. RESULTS: Four of 69 cDNA fragments (3 up-regulated named L1, L2 and L3 and 1 down-regulated named M1 in leiomyoma) were confirmed by Northern analysis. Sequence comparison and Northern analysis proved that L1 is exactly the human ribosomal protein S19. It was present ubiquitously in 13 tissues tested but in various levels and even in different size. L1 was highly expressed in parotidean cystadenocarcinoma, pancreatic cancer and breast cancer examined. No mutations have been found in human uterine leiomyomas (n=6). CONCLUSIONS: hRPS19 overexpression might be a universal signal in rapid cell growth tissues.

Adenovirus-mediated expression of pig α(1,3) galactosyltransferase reconstructs Gal α(1,3) Gal epitope on the surface of human tumor cells

Gal alpha(1, 3) Gal (gal epitope) is a carbohydrate epitope and synthesized in large amount by alpha(1, 3) galactosyltransferase [alpha(1, 3) GT] enzyme on the cells of lower mammalian animals such as pigs and mice. Human has no gal epitope due to the inactivation of alpha(1, 3) GT gene but produces a large amount of antibodies (anti-Gal) which recognize Gal alpha(1, 3) Gal structures specifically. In this study, a replication-deficient recombinant adenoviral vector Ad5sGT containing pig alpha(1, 3) GT cDNA was constructed and characterized. Adenoviral vector-mediated transfer of pig alpha(1, 3) GT gene into human tumor cells such as malignant melanoma A375, stomach cancer SGC-7901, and lung cancer SPC-A-1 was reported for the first time. Results showed that Gal epitope did not increase the sensitivity of human tumor cells to human complement-mediated lysis, although human complement activation and the binding of human IgG and IgM natural antibodies to human tumor cells were enhanced significantly after Ad5sGT transduction. Appearance of gal epitope on the human tumor cells changed the expression of cell surface carbohydrates reacting with Ulex europaeus I (UEA I) lectins, Vicia villosa agglutinin (VVA), Arachis hypogaea agglutinin (PNA), and Glycine max agglutinin (SBA) to different degrees. In addition, no effect of gal epitope on the growth in vitro of human tumor cells was observed in MTT assay.

Applying a highly specific and reproducible cDNA RDA method to clone garlic up-regulated genes in human gastric cancer cells

AIM: To develop and optimize cDNA representational difference analysis (cDNA RDA) method and to identify and clone garlic up-regulated genes in human gastric cancer (HGC) cells. METHODS: We performed cDNA RDA method by using abundant double-stranded cDNA messages provided by two self-constructed cDNA libraries (Allitridi-treated and paternal HGC cell line BGC823 cells cDNA libraries respectively). Bam H I and Xho I restriction sites harbored in the library vector were used to select representations. Northern and Slot blots analyses were employed to identify the obtained difference products. RESULTS: Fragments released from the cDNA library vector after restriction endonuclease digestion acted as good marker indicating the appropriate digestion degree for library DNA. Two novel expressed sequence tags (ESTs) and a recombinant gene were obtained. Slot blots result showed a 8-fold increase of glia-derived nexin/protease nexin 1 (GDN/PN1) gene expression level and 4-fold increase of hepatitis B virus x-interacting protein (XIP) mRNA level in BGC823 cells after Allitridi treatment for 72h. CONCLUSION: Elevated levels of GDN/PN1 and XIP mRNAs induced by Allitridi provide valuable molecular evidence for elucidating the garlic's efficacies against neurodegenerative and inflammatory diseases. Isolation of a recombinant gene and two novel ESTs further show cDNA RDA based on cDNA libraries to be a powerful method with high specificity and reproducibility in cloning differentially expressed genes.

The involvement of p38 MAPK in transforming growth factor β1-induced apoptosis in murine hepatocytes

We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis.

Thansgenic peanut plants obtained by particle bombardment via somatic embryogenesis regeneration system

After pre-culture and treatment of osmosis, cotyledons of immature peanut (Arachis hypogaea L.) zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resistance to hygromycin and a chimeric intron-gus gene. Selection for hygromycin resistant calluses and somatic embryos was initiated at 10th d post-bombardment on medium containing 10-25 mg/L hygromycin. Under continuous selection, hygromycin resistant plantlets were regenerated from somatic embryos and were recovered from nearly 1.6% of the bombarded cotyledons. The presence and integration of foreign DNA in regenerated hygromycin resistant plants was confirmed by PCR (polymerase chain reaction) for the intron-gus gene and by Southern hybridization of the hph gene. GUS enzyme activity was detected in leaflets from transgenic plants but not from control, non-transformed plants. The production of transgenic plants are mainly based on a newly improved somatic embryogenesis regeneration system developed by us.

Blockage of IGF-1R signaling sensitizes urinary bladder cancer cells to mitomycin-mediated cytotoxicity

A major problem which is poorly understood in the management of bladder cancer is low sensitivity to chemotherapy and high recurrence after transurethral resection. Insulin-like growth factor 1 receptor (IGF-1R) signaling plays a very important role in progression, invasion and metastasis of bladder cancer cells. In this study, we investigated whether IGF-1R was involved in the growth stimulating activity and drug resistance of bladder cancer cells. The results showed: The mRNAs of IGF-1, IGF-2 and IGF-1R were strongly expressed in serum-free cultured T24 cell line, whereas normal urothelial cells did not express these factors/receptors or only in trace levels; T24 cell responded far better to growth stimulation by IGF-1 than did normal urothelial cells; blockage of IGF1R by antisense oligodeoxynucleotide (ODN) significantly inhibited the growth of T24 cell and enhanced sensitivity and apoptosis of T24 cells to mitomycin (MMC). These results suggested that blockage of IGF-IR signaling might potentially contribute to the treatment of bladder cancer cells which are insensitive to chemotherapy.

Maternal zinc deficiency impairs brain nestin expression in prenatal and postnatal mice

Effects of maternal dietary zinc deficiency on prenatal and postnatal brain development were investigated in ICR strain mice. From d 1 of pregnancy (E0) until postnatal d 20 (P20), maternal mice were fed experimental diets that contained 1 mg Zn/kg/day (severe zinc deficient, SZD), 5 mg Zn/kg/day (marginal zinc deficient, MZD), 30 mg Zn/kg/day (zinc adequately supplied, ZA) or 100 mg Zn/kg/day (zinc supplemented, ZS and pair-fed, PF). Brains of offspring from these dietary groups were examined at various developmental stages for expression of nestin, an intermediate filament protein found in neural stem cells and young neurons. Immunocytochemistry showed nestin expression in neural tube 10.5 d post citrus (dpc) as well as in the cerebral cortex and neural tube from 10.5 dpc to postnatal d 10 (P10). Nestin immunoreactivities in both brain and neural tube of those zinc-supplemented control groups (ZA, ZS, PF) were stronger than those in zinc-deficient groups (SZD and MZD). Western blot analysis confirmed that nestin levels in pooled brain extracts from each of the zinc-supplemented groups (ZA, ZS, PF) were much higher than those from the zinc-deficient groups (SZD and MZD) from 10.5 dpc to P10. Immunostaining and Western blots showed no detectable nestin in any of the experimental and control group brains after P20. These observations of an association between maternal zinc deficiency and decreased nestin protein levels in brains of offspring suggest that zinc deficiency suppresses development of neural stem cells, an effect which may lead to neuroanatomical and behavioral abnormalities in adults.

基于转录组测序的菜心茎尖组织开花相关基因差异表达分析

【目的】基于转录组测序数据分析鉴定调控菜心抽薹开花相关的候选基因及信号通路,为今后阐明菜心抽薹开花调控分子机制及选育不同熟性菜心品种提供理论参考。【方法】对四九-19号(早熟型)和80天油绿(晚熟型)菜心的七叶期和现蕾期茎尖组织进行转录组测序,比较不同熟性菜心品种间及不同生长时期间的差异表达基因(DEGs),并对其进行GO功能注释及KEGG信号通路富集分析,结合FLOR-ID和UniProt数据库筛选出不同熟性菜心参与调控抽薹开花时间的候选基因及信号通路,通过实时荧光定量PCR验证转录组数据的可靠性。【结果】菜心茎尖组织转录组测序数据为81.93 Gb,经质控过滤后得到536679570条Clean reads,GC含量为47.24%~47.63%,Q20为97.11%~98.00%,Q30为91.97%~94.11%,平均87.98%的Clean reads比对上参考基因组。四九-19号菜心的七叶期和现蕾期间有1965个DEGs,80天油绿菜心的七叶期和现蕾期有6007个DEGs。GO功能注释结果显示,涉及分子功能的DEGs最多,主要注释为蛋白质二聚化活性、血红素结合和四吡咯结合等;其次是生物学过程,主要注释为小分子代谢过程、脂质代谢过程和离子运输等过程;细胞成分类别中,DEGs主要注释为核糖体、细胞器部分、染色体、核小体、蛋白质-DNA复合物和DNA包装复合体。KEGG信号通路富集结果显示,四九-19号菜心七叶期和现蕾期间的DEGs显著(Padj<0.05,下同)富集在光合生物中的碳固定及角质、木栓质和蜡生物合成等通路;80天油绿菜心七叶期和现蕾期间的DEGs显著富集在苯丙素生物合成、DNA复制和植物激素信号转导等通路。四九-19号和80天油绿菜心品种间有750个DEGs,其中16个为开花相关基因,涉及光周期途径、自主途径、赤霉素途径、春化途径、温度途径和年龄途径等,部分开花基因在2个菜心品种中表达量存在明显差异。实时荧光定量PCR检测结果与转录组测序结果相关性较强。【结论】菜心抽薹开花过程受到光周期途径、自主途径和赤霉素途径等关键途径调控,同时受到春化途径、温度途径和年龄途径的影响。虽然2个不同熟性菜心品种开花调控所涉及的途径基本相同,但开花调控途径中的基因响应不一致,导致二者开花时间存在差异。

Effect of all-trans retinoic acid and arsenic trioxide on tissue factor expression in acute promyelocytic leukemia cells

OBJECTIVE: To study the effect of all-trans retinoic acid (ATRA) and arsenic troxide (As2O3) on tissue factor (TF) expression and procoagulant activity (PCA) of acute promyelocytic leukemia (APL) cells in vivo and in vitro. METHODS: PCA from freshly isolated APL blasts from APL patients treated with ATRA or As2O3 was detected using a one-stage clotting assay. TF antigen was detected by ELISA and TF mRNA by RT-PCR. The maturation sensitive (NB4) or resistant subclones (NB4-R1) of the promyelocytic NB4 cell line, as well as U937 cells infected with pMSCV-PML-RARa treated with or without ATRA or As2O3, were also examined. RESULTS: Both ATRA and As2O3 can down-regulate the TF antigen, its mRNA transcription and membrane PCA of APL cells in vivo and in vitro, in a time-dependent manner. The TF antigen level in PML-RARa + U937 cells was significantly higher than that in U937 cells infected with retrovirus vector. Both ATRA and As2O3 can also down-regulate the TF antigen in U937 cells transfected with or without PML-RARa. CONCLUSION: Tissue factor expression and PCA in APL cells may be down-regulated by ATRA and As2O3. By down-regulating TF expression, As2O3 might also be used to improve the DIC-related hemorrhage in APL. Our data indicate that elevated TF antigen in PML-RARa + U937 may be related to the fusion protein PML-RARa. The down-regulating effect of ATRA and As2O3 on TF expression in U937 cells might not involve this fusion protein.

河蚌提取物葡聚糖对软骨细胞Wnt通路的调控作用研究

目的 :探讨河蚌肉提取物葡聚糖HBP-A(anodonta glucan HBP-A)对体外软骨细胞Wnt通路的调控作用。方法:体外培养大鼠软骨细胞,添加IL-1β(10 ng/ml)诱导分化,分为空白组,IL-1β组,IL-1β+IWP-2(5μM,Wnt通路抑制剂)组,IL-1β+HBP-A(0.3 mg/ml)组,IL-1β+IWP-2+HBP-A共5组培养,提取各组细胞RNA和蛋白,采用Rt-PCR检测各组细胞Wnt-3a、β-catenin(24、48、72 h)及MMP-13(72 h)的基因表达;采用Western-blot检测β-catenin、MMP-13、Sox-9和Coll-Ⅱ蛋白的表达水平(48 h)。结果:细胞经IL-1β诱导分化,Wnt-3a基因表达升高,β-catenin以及MMP-13基因和蛋白表达升高,Sox-9和Coll-Ⅱ蛋白表达下调。添加HBP-A干预可以抑制IL-1β诱导下软骨细胞Wnt-3a基因的高表达、β-catenin以及MMP-13基因和蛋白的高表达,上调Sox-9和Ⅱ型胶原蛋白的表达。IWP-2和HBP-A合用时,Wnt-3a、β-catenin基因以及β-catenin蛋白表达最低,Sox-9蛋白表达最高。结论:HBP-A可通过降低Wnt/β-catenin信号通路表达,延缓软骨细胞分化,并且可与Wnt抑制剂协同调节Wnt-3a、β-catenin和Sox-9因子的表达。

尾悬吊模拟失重大鼠肺组织细胞凋亡调控基因的研究

为研究尾悬吊模拟失重大鼠肺组织细胞凋亡调控基因的变化 ,采用尾悬吊模拟失重 ,分为悬吊 7天和 2 1天及相应对照 4组 ,每组 10只健康雄性SD大鼠 ,并采用原位杂交技术检测肺组织bcl 2 /bax的表达情况。发现 7天尾悬吊模拟失重大鼠肺组织bcl 2mRNA水平明显低于对照组 ,两者之间差异有显著性意义 (P <0 0 5 ) ,但 2 1天bcl 2mRNA水平与对照组相比无显著性差异 (P >0 0 5 ) ;7天尾悬吊模拟失重大鼠肺组织baxmRNA水平明显高于对照组 ,两者之间差异有显著性意义(P <0 0 5 ) ,但 2 1天baxmRNA水平与对照组相比亦无显著性差异 (P >0 0 5 )。提示尾悬吊 7天模拟失重大鼠肺组织细胞凋亡调控基因存在变化。

青藤碱抗炎作用机理研究

【目的】通过观察青藤碱对人环氧化酶(COX)、白介素-1β(IL-1β)基因表达的影响,探讨青藤碱的抗炎作用机理。【方法】分离正常人外周血单核细胞(PBMC),体外加药培养,提取细胞总核糖核酸(RNA),采用半定量逆转录聚合酶链反应(RT-PCR)技术,观察青藤碱对脂多糖(LPS)刺激和非LPS刺激状态下环氧化酶及IL-1β基因表达的影响。【结果】青藤碱对COX-1基因表达无明显影响,对COX-2基因表达仅有轻微的抑制作用,而对IL-1β基因表达的抑制作用较强。【结论】青藤碱可能是通过抑制炎症性细胞因子的产生而发挥其抗炎作用。

鹅脂肪甘油三酯脂肪酶和长链脂酰辅酶A合成酶1基因表达差异及其对脂肪沉积和血清脂类代谢的调控

本试验旨在研究脂肪甘油三酯脂肪酶(ATGL)和长链脂酰辅酶A合成酶1(ACSL1)基因在鹅的不同组织器官中的表达差异,并探索2个基因表达对机体脂肪沉积和血清脂类代谢的调控。选取16周龄五龙鹅30只(公母各占1/2),屠宰后用实时荧光定量PCR检测不同组织器官(肝脏、心脏、皮下脂肪、腹部脂肪、胸肌、腿肌、肌胃、腺胃、小肠、肾脏、大脑、肺、脾脏)中A TG L、A CSL1基因表达量。结果表明:1)在鹅的皮下脂肪、腹部脂肪、肝脏、脾脏、肾脏、心脏、胸肌和腿肌中均检测出ATGL和ACSL1基因的表达;ATGL基因在皮下脂肪和腹部脂肪中表达量最高,其次是肝脏和脾脏,在肾脏、心脏、胸肌和腿肌中只有少量表达;ACSL1基因在皮下脂肪、腹部脂肪、肝脏、脾脏中表达量较高,在肾脏、心脏、胸肌和腿肌中有少量表达,而在肌胃、腺胃和肺中几乎不表达。2)ATGL基因表达量与腿肌肌内脂肪率、胸肌肌内脂肪率、腹部脂肪率、胸肌率和腿肌率呈显著或极显著负相关(P<0.05或P<0.01),与皮下脂肪率呈显著正相关(P<0.05);ACSL1基因表达量与腿肌肌内脂肪率、胸肌肌内脂肪率、胸肌率呈正相关(P>0.05),与腿肌率呈显著正相关(P<0.05),与皮下脂肪率呈显著负相关(P<0.05)。3)ATGL基因表达量与血清甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和葡萄糖含量呈显著或极显著正相关(P<0.05或P<0.01);ACSL1基因表达量与血清总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和葡萄糖含量呈负相关(P>0.05),与甘油三酯含量呈显著负相关(P<0.05)。由此可见,ATGL和ACSL1基因在鹅的不同组织器官中的表达具有明显差异性,对机体脂肪沉积和血清脂类代谢具有反向调控作用。

高羊茅组织培养再生体系及GUS基因瞬间表达研究

以成熟种子为外植体,对高羊茅组织培养和植株再生体系进行了优化,分析了不同浓度2,4-D、6-BA和激动素对高羊茅愈伤组织诱导和愈伤组织分化成苗的影响,结果表明:9.0mg/L2,4-D对愈伤组织的诱导效果最佳,0.2mg/L激动素是愈伤组织分化成苗的最适浓度,二者的诱导率和分化率分别达到68.08%和45.83%.在愈伤组织继代培养基中附加1.0mg/L2,4-D、0.5mg/L6-BA和1.25mg/LCuSO4有利于胚性愈伤组织的形成,可以明显促进愈伤组织分化.同时,采用基因枪法将GUS基因导入高羊茅愈伤组织中,通过组织化学染色检测到了GUS瞬间表达活性;并对影响GUS基因瞬间表达的因素进行了分析,以期为提高基因枪法遗传转化效率提供参考.