Genetically engineered mouse(GEM)models are commonly used in biomedical research.Generating GEMs involve complex set of experimental procedures requiring sophisticated equipment and highly skilled technical staff.Beca...Genetically engineered mouse(GEM)models are commonly used in biomedical research.Generating GEMs involve complex set of experimental procedures requiring sophisticated equipment and highly skilled technical staff.Because of these reasons,most research institutes set up centralized core facilities where custom GEMs are created for research groups.Researchers,on the other hand,when they begin thinking about generating GEMs for their research,several questions arise in their minds.For example,what type of model(s)would be best useful for my research,how do I design them,what are the latest technologies and tools available for developing my model(s),and finally how to breed GEMs in my research.As there are several considerations and options in mouse designs,and as it is an expensive and time-consuming endeavor,careful planning upfront can ensure the highest chance of success.In this article,we provide brief answers to several frequently asked questions that arise when researchers begin thinking about generating mouse model(s)for their work.展开更多
The crosstalk between megakaryocytic lineage cells and the skeletal system has just begun to be explored but remains largely elusive.Using conditional gene knockout mouse models,we demonstrated that loss of Beclin 1(B...The crosstalk between megakaryocytic lineage cells and the skeletal system has just begun to be explored but remains largely elusive.Using conditional gene knockout mouse models,we demonstrated that loss of Beclin 1(Becn1),a major regulator of mammalian autophagy,exclusively in the megakaryocytic lineage disrupted autophagy in platelets but did not compromise megakaryopoiesis or the formation and function of platelets.Unexpectedly,conditional Becn1 deletion in male mice led to a remarkable increase in bone mass with improved bone quality,in association with a decrease in sex hormone binding globulin(SHBG)and an increase in free testosterone(FT).In vivo Becn1 overexpression in megakaryocytic lineage-specific cells reduced bone mass and quality,along with an increase in SHBG and a decrease in FT.Transplantation of wild-type bone marrow cells into megakaryocytic lineage Becn1-deficient male mice restored bone mass and normalized SHBG and FT.Furthermore,bilateral orchiectomy of Becn1^(f/f);Pf4-iCre mice,which are crippled with the production of testosterone,resulted in a reduction in bone mass and quality,whereas in vivo overexpression of SHBG,specifically in the liver of Becn1^(f/f);Pf4-iCre mice,decreased FT and reduced bone mass and quality.In addition,metformin treatment,which induces SHBG expression,reduced FT and normalized bone mass in Becn1^(f/f);Pf4-iCre mice.We thus concluded that Becn1 of the megakaryocytic lineage is dispensable locally for platelet hemostasis but limits bone mass by increasing SHBG,which in turn reduces the FT of male mice.Our findings highlight a mechanism by which Becn1 from megakaryocytic lineage cells distally balances bone growth.展开更多
基金We thank D.D.Meigs(University of Nebraska Medical Center)and Tonya Cejka(freelance English editor)for editing assistance.C.B.G.is funded by NIH grants R35HG010719,R21GM129559,R21AI143394 and R21DA046831.M.O.is funded by 2016–2017 Tokai University School of Medicine Project Research,the Research Aid from the Institute of Medical Sciences in Tokai University,Grant-in-Aid for Scientific Research(25290035)from MEXTa Grant-in-Aid for Challenging Exploratory Research(15K14371)from JSPS.
文摘Genetically engineered mouse(GEM)models are commonly used in biomedical research.Generating GEMs involve complex set of experimental procedures requiring sophisticated equipment and highly skilled technical staff.Because of these reasons,most research institutes set up centralized core facilities where custom GEMs are created for research groups.Researchers,on the other hand,when they begin thinking about generating GEMs for their research,several questions arise in their minds.For example,what type of model(s)would be best useful for my research,how do I design them,what are the latest technologies and tools available for developing my model(s),and finally how to breed GEMs in my research.As there are several considerations and options in mouse designs,and as it is an expensive and time-consuming endeavor,careful planning upfront can ensure the highest chance of success.In this article,we provide brief answers to several frequently asked questions that arise when researchers begin thinking about generating mouse model(s)for their work.
基金supported in part by grants from the National Natural Science Foundation of China(No.81673093,No.82170227,No.91649113,No.82470165,No.82000121,No.31771640)the Jiangsu Science and Technology Department(No.SBK20200191)+1 种基金the State Key Laboratory of Radiation Medicine and Protection of Soochow University(No.GZC00201)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘The crosstalk between megakaryocytic lineage cells and the skeletal system has just begun to be explored but remains largely elusive.Using conditional gene knockout mouse models,we demonstrated that loss of Beclin 1(Becn1),a major regulator of mammalian autophagy,exclusively in the megakaryocytic lineage disrupted autophagy in platelets but did not compromise megakaryopoiesis or the formation and function of platelets.Unexpectedly,conditional Becn1 deletion in male mice led to a remarkable increase in bone mass with improved bone quality,in association with a decrease in sex hormone binding globulin(SHBG)and an increase in free testosterone(FT).In vivo Becn1 overexpression in megakaryocytic lineage-specific cells reduced bone mass and quality,along with an increase in SHBG and a decrease in FT.Transplantation of wild-type bone marrow cells into megakaryocytic lineage Becn1-deficient male mice restored bone mass and normalized SHBG and FT.Furthermore,bilateral orchiectomy of Becn1^(f/f);Pf4-iCre mice,which are crippled with the production of testosterone,resulted in a reduction in bone mass and quality,whereas in vivo overexpression of SHBG,specifically in the liver of Becn1^(f/f);Pf4-iCre mice,decreased FT and reduced bone mass and quality.In addition,metformin treatment,which induces SHBG expression,reduced FT and normalized bone mass in Becn1^(f/f);Pf4-iCre mice.We thus concluded that Becn1 of the megakaryocytic lineage is dispensable locally for platelet hemostasis but limits bone mass by increasing SHBG,which in turn reduces the FT of male mice.Our findings highlight a mechanism by which Becn1 from megakaryocytic lineage cells distally balances bone growth.
