The classic method for gene knockout (KO) is based on homologous recombination (HR) and embryonic stem cell technique (Gerlai,1996).Actually,the procedure of homologous replacement is complicated and time consuming,al...The classic method for gene knockout (KO) is based on homologous recombination (HR) and embryonic stem cell technique (Gerlai,1996).Actually,the procedure of homologous replacement is complicated and time consuming,although it has been popular during the past decades.Recent years,genome editing which can cause DNA sequence-specific mutations in the genomes of cellular展开更多
Screening gene function in vivo is a powerful approach to discover novel drug targets. We present high-throughput screening （HTS） data for 3 762 distinct global gene knockout （KO） mouse lines with viable adult hom...Screening gene function in vivo is a powerful approach to discover novel drug targets. We present high-throughput screening （HTS） data for 3 762 distinct global gene knockout （KO） mouse lines with viable adult homozygous mice generated using either gene-trap or homologous recombination technologies. Bone mass was determined from DEXA scans of male and female mice at 14 weeks of age and by microCT analyses of bones from male mice at 16 weeks of age. Wild-type （WT） cagemates/littermates were examined for each gene KO. Lethality was observed in an additional 850 KO lines. Since primary HTS are susceptible to false positive findings, additional cohorts of mice from KO lines with intriguing HTS bone data were examined. Aging, ovariectomy, histomorphometry and bone strength studies were performed and possible non-skeletal phenotypes were explored. Together, these screens identified multiple genes affecting bone mass： 23 previously reported genes （Calcr, Cebpb, Crtap, Dcstamp, Dkkl, Duoxa2, Enppl, Fgf23, Kissl/Kisslr, Kl （Klotho）, Lrp5, Mstn, Neol, Npr2, Ostml, Postn, Sfrp4, S1c30a5, Sic39a13, Sost, Sumf1, Src, Wnt10b）, five novel genes extensively characterized （Cldn18, Fam20c, Lrrkl, Sgpll, Wnt16）, five novel genes with preliminary characterization （Agpat2, RassfS, Slc10a7, Stc26a7, Slc30a10） and three novel undisclosed genes coding for potential osteoporosis drug targets.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supported by the National Key Research and Development Plan of China(2017YFD0501602)the Support Project of High-level Teachers in Beijing Municipal Universities in the Period of 13th Five Plan(IDHT20170516)
文摘The classic method for gene knockout (KO) is based on homologous recombination (HR) and embryonic stem cell technique (Gerlai,1996).Actually,the procedure of homologous replacement is complicated and time consuming,although it has been popular during the past decades.Recent years,genome editing which can cause DNA sequence-specific mutations in the genomes of cellular
文摘Screening gene function in vivo is a powerful approach to discover novel drug targets. We present high-throughput screening （HTS） data for 3 762 distinct global gene knockout （KO） mouse lines with viable adult homozygous mice generated using either gene-trap or homologous recombination technologies. Bone mass was determined from DEXA scans of male and female mice at 14 weeks of age and by microCT analyses of bones from male mice at 16 weeks of age. Wild-type （WT） cagemates/littermates were examined for each gene KO. Lethality was observed in an additional 850 KO lines. Since primary HTS are susceptible to false positive findings, additional cohorts of mice from KO lines with intriguing HTS bone data were examined. Aging, ovariectomy, histomorphometry and bone strength studies were performed and possible non-skeletal phenotypes were explored. Together, these screens identified multiple genes affecting bone mass： 23 previously reported genes （Calcr, Cebpb, Crtap, Dcstamp, Dkkl, Duoxa2, Enppl, Fgf23, Kissl/Kisslr, Kl （Klotho）, Lrp5, Mstn, Neol, Npr2, Ostml, Postn, Sfrp4, S1c30a5, Sic39a13, Sost, Sumf1, Src, Wnt10b）, five novel genes extensively characterized （Cldn18, Fam20c, Lrrkl, Sgpll, Wnt16）, five novel genes with preliminary characterization （Agpat2, RassfS, Slc10a7, Stc26a7, Slc30a10） and three novel undisclosed genes coding for potential osteoporosis drug targets.
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.
