Publications by authors named "Qing Zhang Li"

In dairy cows, the extracellular microenvironment varies significantly from the virgin state to lactation. The function of integrin α6β4 is dependent on cell type and extracellular microenvironment, and the precise expression profile of α6β4 and its effects on mammary development remain to be determined. In the present study, real-time PCR and immunohistochemistry were used to analyze the expression and localization of integrin α6β4 in Holstein dairy cow mammary glands.

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Sterol regulatory element-binding proteins (SREBPs) belong to a family of nuclear transcription factors. The question of which is the most important positive regulator in milk fat synthesis in dairy cow mammary epithelial cells (DCMECs) between SREBPs or other nuclear transcription factors, such as peroxisome proliferator-activated receptor γ (PPARγ), remains a controversial one. Recent studies have found that mTORC1 (the mammalian target of rapamycin C1) regulates SREBP1 to promote fat synthesis.

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Milk fat is the major energy component of milk, and regulation of its production relies on transcription factors sterol regulatory element-binding protein 1 (SREBP1) and peroxisome proliferator-activated receptor gamma (PPARγ). As one of the target genes of SREBP1 and PPARγ, fatty acid-binding protein 3(FABP3) is the main protein allowing for rapid diffusion and selective targeting of long-chain fatty acids toward specific organelles for metabolism. Whether FABP3 plays an important role in milk fat synthesis signaling pathway is largely unknown.

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Suppressor of cytokine signaling 3 (SOCS3) is a cytokine-induced negative feedback-loop regulator of cytokine signaling. More and more evidence has proved it to be an inhibitor of signal transducers and activators of transcription 5 (STAT5). Here, we used dairy cow mammary epithelial cells (DCMECs) to analyze the function of SOCS3 and the interaction between SOCS3 and STAT5a.

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The antibacterial peptide Cecropin B (CB), isolated from the giant silk moth, has been shown to effectively eliminate bacteria. In this study, the effects of transgenic CB on dairy goat mammary epithelial cells (DGMECs) and dairy goat mammary gland were investigated. The DNA of CB from silkworm was amplified by reverse transcription PCR (RT-PCR) and then fused to the eukaryotic expression vector pECFP-C1.

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L-Lysine (L-Lys) is an essential amino acid that plays fundamental roles in protein synthesis. Many nuclear phosphorylated proteins such as Stat5 and mTOR regulate milk protein synthesis. However, the details of milk protein synthesis control at the transcript and translational levels are not well known.

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MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate the expression of target genes at the post-transcriptional level by transcript degradation or translational inhibition. The role of bta-miR-15a in bovine mammary gland hasn’t been reported. Using miRNAs prediction software, GHR gene was predicted to be a potential target of bta-miR-15a.

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Signal transducer and activator of transcription 5a (Stat5a) transduces signals of extracellular cytokines and growth factors to the nucleus of mammary gland epithelial cells and thereby regulates gene transcription during pregnancy, lactation, and weaning. However, its function on the milk production of dairy cows needs further investigation. In this experiment, the effects of Stat5a on lactation ability of dairy cow mammary gland epithelial cells (DCMECs) were analyzed.

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Estrogen regulates a variety of physiological processes, including mammary gland growth, morphogenesis of the mammary gland, proliferation and differentiation, and elevating the expression of milk proteins. Many nuclear phosphorylated proteins such as pStat5 and mTOR regulate milk protein synthesis. But the detail of milk protein synthesis controlled at the transcript level and posttranslational level is not well-known.

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To study milk synthesis in dairy goat mammary gland, we had established an in vitro lactating dairy goat mammary epithelial cell (DGMEC) line. Mammary tissues of Guan Zhong dairy goats at 35 d of lactation were dispersed and cultured in a medium containing epithelial growth factor, insulin-like growth factor-1, insulin transferrin serum, and fetal bovine serum. Epithelial cells were enriched by digesting with 0.

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The objective of the research was to study the changes of the major organelles, endoplasmic reticulum (ER) and mitochondria, in mammary epithelial cells of the Chinese Holstein dairy cow during mammogenesis. For this purpose, a mammary epithelial cell bank was established from 9 selected Chinese Holstein dairy cows using collagenase I digestion and attachment culture biotechniques. This cell bank included 9 samples at stages of pregnancy, lactation and involution.

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Heregulin-alpha (HRGalpha) is a cytokine secreted by the mammary mesenchyme, adjacent to lobuloalveolar structures. To understand the role of HRGalpha and its receptors in mammary glands, and the underlying mechanisms, we performed this study to determine the expression and localization of HRGalpha and its receptors ErbB2 and ErbB3. We also determined the role of HRGalpha in the development of mammary glands, beta-casein expression and secretion, Rab3A protein expression and the phosphorylation of HRGalpha signaling molecules using confocal laser scanning microscopy, tissue culture, capillary electrophoresis, Western blotting and enzyme-linked immunosorbent assays.

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Mammary glands undergo functional and metabolic changes during virgin, lactation and dry periods. A total of 122 genes were identified as differentially expressed, including 79 up-regulated and 43 down-regulated genes during lactation compared with virgin and dry periods. Gene ontology analysis showed the functional classification of the up-regulated genes in lactation, including transport, biosynthetic process, signal transduction, catalytic activity, immune system process, cell death, and positive regulation of the developmental process.

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Fragile X syndrome (FXS) is one of the most prevalent mental retardations. It is mainly caused by the loss of fragile X mental retardation protein (FMRP). FMRP is an RNA binding protein and can regulate the translation of its binding RNA, thus regulate several signaling pathways.

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Leptin is an autocrine and paracrine factor which affects the development of duct, formation of gland alveolus, expression of milk protein gene and onset involution of mammary gland. In order to know the function and mechanism of leptin in mammary gland, the protein expression and localization of leptin and its long form receptor (OB-Rb) were detected by a confocal laser scanning microscope. To study the impacts of leptin on mammary gland and leptin signal transduction pathway in pregnancy-, lactation-and involution-stage mammary gland, explants were cultured and Western blotting was used.

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The protein kinase Cs (PKCs) are a family of Ser/Thr protein kinases categorized into three subfamilies: classical, novel, and atypical. The phosphorylation of PKC in germ cells is not well defined. In this study, we described the subcellular localization of phopho-PKC in the process of mouse oocyte maturation, fertilization, and early embryonic mitosis.

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The progressive morphological changes to early stage Taenia solium cysticerci following the treatment of pigs with a single therapeutic dose of oxfendazole (30 mg/kg), are described. On Day 1 after treatment, no obvious changes occurred in the general appearance of the larvae but alternations were seen by electron microscope, with an apparent reduction in the number of microtriches, and a complete disappearance of the tegument. Numerous granules were seen to have accumulated in the tegument cells.

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Synopsis of recent research by authors named "Qing Zhang Li"

  • - Qing Zhang Li's research primarily focuses on the molecular mechanisms underlying milk fat and protein synthesis in dairy cattle and goats, examining the roles of various proteins and signaling pathways involved in mammary gland development and function.
  • - Key findings include the significance of integrin α6β4 in mammary development, the regulation of milk fat synthesis by SREBP1 and FABP3, and the impact of signaling pathways like JAK2/STAT5 on lactation processes.
  • - The author's work also explores innovative approaches such as the application of antimicrobial peptides to combat mastitis in dairy animals and the establishment of cell lines for in vitro studies on milk synthesis.

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