It is suggested that Δ6 fatty acid desaturase(FAD) plays a critical role in the biosynthesis of polyunsaturated fatty acids in plants and microalgae. But why does it adapt to the changed environments such as nitrogen...It is suggested that Δ6 fatty acid desaturase(FAD) plays a critical role in the biosynthesis of polyunsaturated fatty acids in plants and microalgae. But why does it adapt to the changed environments such as nitrogen starvation is seldom understood. One Δ6 FAD gene( MiD6 fad) from an arachidonic acidrich microalga M yrmecia incisa Reisigl(Chlorophyta) was first heterologously expressed in S accharomyces cerevisiae for the identification of function. The fatty acid profile of transgenic yeast detected by gas chromatography-mass spectrometry illustrated that the enzyme MiD6 FAD could convert linoleic and ?-linolenic acids to γ-linolenic and stearidonic acids, respectively, demonstrating that M iD6 fad encoded a Δ6 FAD. A 1 965-bp fragment of the cloned 2 347-bp 5′-upstream region of M iD6 fad was next subcloned and fused upstream with green fluorescent protein(GFP) gene to replace the GAL1 promoter of the vector pYES2. The generated construct was transformed into S. cerevisiae for function determination. Confocal microscopic images of the transformed line illustrated that this inserted fragment could drive GFP expression, which was further verified by fluorescence intensity quantification and Western blot analysis using antiGFP antibody. The conversion efficiency(approximately 2%-3%) of MiD6 FAD was much lower than the reported ? 3 FAD and Δ6 elongase in this microalga, suggesting that MiD6 FAD catalysed the possible ratelimiting step for ArA biosynthesis. The presence of several putative c is-acting regulatory elements in this identified promoter sheds new light on the regulation mechanism research of Δ6 FAD transcription for the ArA production in M. incisa in changing environmental factors.展开更多
Basophils,which are considered as redundant relatives of mast cells and the rarest granulocytes in peripheral circulation,have been neglected by researchers in the past decades.Previous studies have revealed their vit...Basophils,which are considered as redundant relatives of mast cells and the rarest granulocytes in peripheral circulation,have been neglected by researchers in the past decades.Previous studies have revealed their vital roles in allergic diseases and parasitic infections.Intriguingly,recent studies even reported that basophils might be associated with cancer development,as activated basophils synthesize and release a variety of cytokines and chemokines in response to cancers.However,it is still subject to debate whether basophils function as tumor-protecting or tumor-promoting components;the answer may depend on the tumor biology and the microenvironment.Herein,we reviewed the role of basophils in cancers,and highlighted some potential and promising therapeutic strategies.展开更多
Pancreatic ductal adenocarcinoma is the known kind of tumor biologically featured as high malignant degree, lack of effective methods for diagnosis and treatment, which reflects its unpleasant prognosis. Recently, wit...Pancreatic ductal adenocarcinoma is the known kind of tumor biologically featured as high malignant degree, lack of effective methods for diagnosis and treatment, which reflects its unpleasant prognosis. Recently, with the breakthrough of burgeoning therapeutic methods, the flush of dawn for pancreatic cancer nearly arrives. Nowadays, besides surgery, neoadjuvant chemoradiotherapy, tumor vaccine therapy, and immunotherapy all show their active situation and obtain certain clinical efficacy, but that is still limited to pancreatic cancer. However, the appearance and development of programmed cell death-1 (PD-1) immune checkpoint inhibitor may final improve survival of pancreatic cancer. This article aims to deeply understand the value of PD-1 immune checkpoint inhibitor in pancreatic cancer and validly provide the evidence for treatment by means of performing a systematic review on the current status in the fields of the mechanism and application of anti-PD-1 in pancreatic cancer, associations with surgery, PD- 1-related side effects and prospections.展开更多
基金Supported by the National Natural Science Foundation of China(No.31172389)the Special Project of Marine Renewable Energy from the State Oceanic Administration(No.SHME2011SW02)the Shanghai Universities Peak Discipline Project of Aquaculture
文摘It is suggested that Δ6 fatty acid desaturase(FAD) plays a critical role in the biosynthesis of polyunsaturated fatty acids in plants and microalgae. But why does it adapt to the changed environments such as nitrogen starvation is seldom understood. One Δ6 FAD gene( MiD6 fad) from an arachidonic acidrich microalga M yrmecia incisa Reisigl(Chlorophyta) was first heterologously expressed in S accharomyces cerevisiae for the identification of function. The fatty acid profile of transgenic yeast detected by gas chromatography-mass spectrometry illustrated that the enzyme MiD6 FAD could convert linoleic and ?-linolenic acids to γ-linolenic and stearidonic acids, respectively, demonstrating that M iD6 fad encoded a Δ6 FAD. A 1 965-bp fragment of the cloned 2 347-bp 5′-upstream region of M iD6 fad was next subcloned and fused upstream with green fluorescent protein(GFP) gene to replace the GAL1 promoter of the vector pYES2. The generated construct was transformed into S. cerevisiae for function determination. Confocal microscopic images of the transformed line illustrated that this inserted fragment could drive GFP expression, which was further verified by fluorescence intensity quantification and Western blot analysis using antiGFP antibody. The conversion efficiency(approximately 2%-3%) of MiD6 FAD was much lower than the reported ? 3 FAD and Δ6 elongase in this microalga, suggesting that MiD6 FAD catalysed the possible ratelimiting step for ArA biosynthesis. The presence of several putative c is-acting regulatory elements in this identified promoter sheds new light on the regulation mechanism research of Δ6 FAD transcription for the ArA production in M. incisa in changing environmental factors.
基金supported by the Shanghai Sailing Program(No.21YF1407100)the China Postdoctoral Science Foundation(No.2021M690037)+1 种基金the National Natural Science Foundation of China(Nos.82103409 and 81773068)the National Key R&D Program of China(No.2019YFC1315902)。
文摘Basophils,which are considered as redundant relatives of mast cells and the rarest granulocytes in peripheral circulation,have been neglected by researchers in the past decades.Previous studies have revealed their vital roles in allergic diseases and parasitic infections.Intriguingly,recent studies even reported that basophils might be associated with cancer development,as activated basophils synthesize and release a variety of cytokines and chemokines in response to cancers.However,it is still subject to debate whether basophils function as tumor-protecting or tumor-promoting components;the answer may depend on the tumor biology and the microenvironment.Herein,we reviewed the role of basophils in cancers,and highlighted some potential and promising therapeutic strategies.
文摘Pancreatic ductal adenocarcinoma is the known kind of tumor biologically featured as high malignant degree, lack of effective methods for diagnosis and treatment, which reflects its unpleasant prognosis. Recently, with the breakthrough of burgeoning therapeutic methods, the flush of dawn for pancreatic cancer nearly arrives. Nowadays, besides surgery, neoadjuvant chemoradiotherapy, tumor vaccine therapy, and immunotherapy all show their active situation and obtain certain clinical efficacy, but that is still limited to pancreatic cancer. However, the appearance and development of programmed cell death-1 (PD-1) immune checkpoint inhibitor may final improve survival of pancreatic cancer. This article aims to deeply understand the value of PD-1 immune checkpoint inhibitor in pancreatic cancer and validly provide the evidence for treatment by means of performing a systematic review on the current status in the fields of the mechanism and application of anti-PD-1 in pancreatic cancer, associations with surgery, PD- 1-related side effects and prospections.
