As a specific type of asthenoteratozoospermia,multiple morphological abnormalities of the sperm flagella(MMAF)is characterized by composite abnormalities,including absent,short,coiled,angulation,and irregular-caliber ...As a specific type of asthenoteratozoospermia,multiple morphological abnormalities of the sperm flagella(MMAF)is characterized by composite abnormalities,including absent,short,coiled,angulation,and irregular-caliber flagella.Mutations in cilia-and flagella-associated protein 43(CFAP43)are one of the main causative factors of MMAF established to date.To identify whether there are other CFAP43 mutations related to MMAF and to determine the clinical outcomes of assisted reproductive technology for patients with MMAF harboring different mutations,we recruited and screened 30 MMAF-affected Chinese men using a 22-gene next-generation sequencing panel.After systematic analysis,seven mutations in CFAP43,including five novel mutations and two previously reported mutations,were identified from four families and related to MMAF in an autosomal recessive pattern.Papanicolaou staining,immunofluorescence,and electronic microscopy further clarified the semen characteristics a nd abnormal sperm morphologies,including disorganized axonemal and peri-axonemal structures,of the CFAP43-deficient men.The female partners of two patients were pregnant after undergoing assisted reproductive technology through intracytoplasmic sperm injection,and one of them successfully gave birth to a healthy boy.This study significantly expands the mutant spectrum of CFAP43,and together with the available information regarding male infertility and MMAF,provides new information for the genetic diagnosis and counseling of MMAF in the future.展开更多
Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the ...Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the underlying genetic factors responsible for the majority of MMAF cases are still largely unknown.The glutamine-rich 2(QRICH2)gene plays an essential role in the development of sperm flagella by regulating the expression of essential sperm flagellar biogenesis-associated proteins,and genetic variants of QRICH2 have been identified as the primary cause of MMAF in humans and mice.Here,we recruited a Pakistani consanguineous family to identify the genetic variant causing infertility in patients with MMAF.Whole-exome sequencing and Sanger sequencing were conducted to identify potentially pathogenic variants causing MMAF in infertile patients.Hematoxylin and eosin(HE)staining was performed to analyze sperm morphology.Quantitative polymerase chain reaction,western blot,and immunofluorescence staining analyses were conducted to observe the expression of QRICH2 in spermatozoa.A novel homozygous missense variant(c.4618C>T)in QRICH2 was identified in the affected patients.Morphological analysis of spermatozoa revealed the MMAF phenotype in infertile patients.qPCR revealed a significant reduction in the level of sperm QRICH2 mRNA,and immunofluorescence staining revealed a lack of sperm QRICH2 expression.Additionally,patients harboring a homozygous QRICH2 mutation presented reduced expression of outer dense fiber 2(ODF2)in sperm,whereas sperm expression of A-kinase anchor protein 4(AKAP4)was normal.These findings expand our understanding of the genetic causes of MMAF-associated male infertility and emphasize the importance of genetic counseling.展开更多
The structural integrity of the sperm flagellum is essential for proper sperm function.Flagellar defects can result in male infertility,yet the precise mechanisms underlying this relationship are not fully understood....The structural integrity of the sperm flagellum is essential for proper sperm function.Flagellar defects can result in male infertility,yet the precise mechanisms underlying this relationship are not fully understood.CCDC181,a coiled-coil domain-containing protein,is known to localize on sperm flagella and at the basal regions of motile cilia.Despite this knowledge,the specific functions of CCDC181 in flagellum biogenesis remain unclear.In this study,Ccdc181 knockout mice were generated.The absence of CCDC181 led to defective sperm head shaping and flagellum formation.Furthermore,the Ccdc181 knockout mice exhibited extremely low sperm counts,grossly aberrant sperm morphologies,markedly diminished sperm motility,and typical multiple morphological abnormalities of the flagella(MMAF).Additionally,an interaction between CCDC181 and the MMAF-related protein LRRC46 was identified,with CCDC181 regulating the localization of LRRC46 within sperm flagella.These findings suggest that CCDC181 plays a crucial role in both manchette formation and sperm flagellum biogenesis.展开更多
Cytosine base editing achieves C·G-to-T·A substitutions and can convert four codons(CAA/CAG/CGA/TGG)into STOP-codons(induction of STOP-codons,iSTOP)to knock out genes with reduced mosaicism.iSTOP enables dir...Cytosine base editing achieves C·G-to-T·A substitutions and can convert four codons(CAA/CAG/CGA/TGG)into STOP-codons(induction of STOP-codons,iSTOP)to knock out genes with reduced mosaicism.iSTOP enables direct phenotyping in founders’somatic cells,but it remains unknown whether this works in founders’germ cells so as to rapidly reveal novel genes for fertility.Here,we initially establish that iSTOP in mouse zygotes enables functional characterization of known genes in founders’germ cells:Cfap43-iSTOP male founders manifest expected sperm features resembling human“multiple morphological abnormalities of the flagella”syndrome(i.e.,MMAF-like features),while oocytes of Zp3-iSTOP female founders have no zona pellucida.We further illustrate iSTOP’s utility for dissecting the functions of unknown genes with Ccdc183,observing MMAF-like features and male infertility in Ccdc183-iSTOP founders,phenotypes concordant with those of Ccdc183-KO offspring.We ultimately establish that CCDC183 is essential for sperm morphogenesis through regulating the assembly of outer dynein arms and participating in the intra-flagellar transport.Our study demonstrates iSTOP as an efficient tool for direct reproductive disease modeling and phenotyping in germ cells of the founder generation,and rapidly reveals the essentiality of Ccdc183 in fertility,thus providing a time-saving approach for validating genetic defects(like nonsense mutations)for human infertility.展开更多
During spermiogenesis,haploid spermatids undergo dramatic morphological changes to form slender sperm flagella and cap-like acrosomes,which are required for successful fertilization.Severe deformities in flagella caus...During spermiogenesis,haploid spermatids undergo dramatic morphological changes to form slender sperm flagella and cap-like acrosomes,which are required for successful fertilization.Severe deformities in flagella cause a male infertility syndrome,multiple morphological abnormalities of the flagella(MMAF),while acrosomal hypoplasia in some cases leads to sub-optimal embryonic developmental potential.However,evidence regarding the occurrence of acrosomal hypoplasia in MMAF is limited.Here,we report the generation of base-edited mice knocked out for coiled-coil domain-containing 38(Ccdc38)via inducing a nonsense mutation and find that the males are infertile.The Ccdc38-KO sperm display acrosomal hypoplasia and typical MMAF phenotypes.We find that the acrosomal membrane is loosely anchored to the nucleus and fibrous sheaths are disorganized in Ccdc38-KO sperm.Further analyses reveal that Ccdc38 knockout causes a decreased level of TEKT3,a protein associated with acrosome biogenesis,in testes and an aberrant distribution of TEKT3 in sperm.We finally show that intracytoplasmic sperm injection overcomes Ccdc38-related infertility.Our study thus reveals a previously unknown role for CCDC38 in acrosome biogenesis and provides additional evidence for the occurrence of acrosomal hypoplasia in MMAF.展开更多
This study aimed to identify genetic causes responsible for multiple morphological abnormalities of the sperm flagella(MMAF)in the Han Chinese population.Three primary infertile males with completely immobile sperm an...This study aimed to identify genetic causes responsible for multiple morphological abnormalities of the sperm flagella(MMAF)in the Han Chinese population.Three primary infertile males with completely immobile sperm and MMAF were enrolled.Whole-exome sequencing and Sanger sequencing were performed to identify disease-causing genes.Subsequently,morphological and ultrastructural analyses of sperm flagella were investigated.The probable impact of genetic variants on protein function was analyzed by online bioinformatic tools and immunofluorescence assay.Three patients with dynein axonemal heavy chain 1(DNAH1)gene compound heterozygous variations were identified.DNAH1 c.7435C>T,p.R2479X and c.10757T>C,p.F3586S were identified in the patient from Family 1,c.11726_11727delCT,p.P3909fs and c.12154delC,p.L4052fs were found in the patient from Family 2,and c.10627-3C>G and c.11726_11727delCT,p.P3909fs existed in the patient from Family 3.Four of these variations have not been reported,and all the mutations showed pathogenicity by functional effect predictions.The absence of the center pair and disorganization of the fibrous sheath were present in sperm flagella at the ultrastructural level.Moreover,the expression of DNAH1 was absent in spermatozoa from the participants,validating the pathogenicity of the variants.All three couples have undergone intracytoplasmic sperm injection(ICSI),and two couples of them became pregnant after the treatment.In conclusion,the newly identified DNAH1 mutations can expand the mutational and phenotypic spectrum of MMAF genes and provide a theoretical basis for genetic diagnosis in MMAF patients.It is recommended to conduct genetic screening in male infertility patients with MMAF and provide rational genetic counseling,and ICSI might be an optimal strategy to help with fertilization and conception for patients with DNAH1 mutations.展开更多
Impaired flagellar development and impaired motility of sperm is a cause of infertility in males. Several genes, including those of the AKAP, CCDC, CFAP, and DNAH families, among others, are involved in the‘‘multipl...Impaired flagellar development and impaired motility of sperm is a cause of infertility in males. Several genes, including those of the AKAP, CCDC, CFAP, and DNAH families, among others, are involved in the‘‘multiple morphological abnormalities of the flagella"(MMAF) phenotype;these are the most common causes of male infertility. The Cilia-and flagella-associated protein(CFAP) family includes six members reported to cause MMAF phenotypes: CFAP43, CFAP44, CFAP69, CFAP65, CFAP70, and CFAP251. Here, we found that cilia-and flagella-associated protein 61(Cfap61) is highly expressed specifically in murine testes and show that the Cfap61-knockout male mice demonstrate MMAF phenotype, including sperm with short, coiled, and irregular flagella. Deletion of Cfap61 resulted in severe morphological and behavior abnormalities in sperm, reduced total sperm counts, impaired sperm motility, and led to male infertility.Notably, absence of Cfap61 impaired sperm flagella ultrastructural abnormalities on account of numerous distortions in multiple flagellum components. Immunostaining experiments in wild-type mice and healthy adult humans indicated that Cfap61 is initially localized at the neck of sperm, where it potentially functions in flagellum formation, and is later localized to the midpiece of the sperm. Thus, our study provides compelling evidence that dysregulation of Cfap61 affects sperm flagellum development and induces male infertility in mice. Further investigations of the CFAP61 gene in humans alongside clinical evidence showing MMAF phenotype in humans should contribute to our understanding of developmental processes underlying sperm flagellum formation and the pathogenic mechanisms that cause male infertility.展开更多
基金the Natural Science Foundation of Chongqing(CSTC2021JCYJ-MSXMX0722)Chongqing Health Center for Women and Children(2020YJMS01).
文摘As a specific type of asthenoteratozoospermia,multiple morphological abnormalities of the sperm flagella(MMAF)is characterized by composite abnormalities,including absent,short,coiled,angulation,and irregular-caliber flagella.Mutations in cilia-and flagella-associated protein 43(CFAP43)are one of the main causative factors of MMAF established to date.To identify whether there are other CFAP43 mutations related to MMAF and to determine the clinical outcomes of assisted reproductive technology for patients with MMAF harboring different mutations,we recruited and screened 30 MMAF-affected Chinese men using a 22-gene next-generation sequencing panel.After systematic analysis,seven mutations in CFAP43,including five novel mutations and two previously reported mutations,were identified from four families and related to MMAF in an autosomal recessive pattern.Papanicolaou staining,immunofluorescence,and electronic microscopy further clarified the semen characteristics a nd abnormal sperm morphologies,including disorganized axonemal and peri-axonemal structures,of the CFAP43-deficient men.The female partners of two patients were pregnant after undergoing assisted reproductive technology through intracytoplasmic sperm injection,and one of them successfully gave birth to a healthy boy.This study significantly expands the mutant spectrum of CFAP43,and together with the available information regarding male infertility and MMAF,provides new information for the genetic diagnosis and counseling of MMAF in the future.
基金supported by the National Key Research and Development Program of China(2021YFC2700202,2022YFA0806303 and 2022YFC2702601)the Global Select Project of the Institute of Health and Medicine,Hefei Comprehensive National Science Center(DJK-LX-2022010)+1 种基金USTC Research Funds of the Double First-Class Initiative(the Joint Fund for New Medicine of USTC)(YD9100002034)the Fundamental Research Funds for the Central Universities(WK9100000004).
文摘Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the underlying genetic factors responsible for the majority of MMAF cases are still largely unknown.The glutamine-rich 2(QRICH2)gene plays an essential role in the development of sperm flagella by regulating the expression of essential sperm flagellar biogenesis-associated proteins,and genetic variants of QRICH2 have been identified as the primary cause of MMAF in humans and mice.Here,we recruited a Pakistani consanguineous family to identify the genetic variant causing infertility in patients with MMAF.Whole-exome sequencing and Sanger sequencing were conducted to identify potentially pathogenic variants causing MMAF in infertile patients.Hematoxylin and eosin(HE)staining was performed to analyze sperm morphology.Quantitative polymerase chain reaction,western blot,and immunofluorescence staining analyses were conducted to observe the expression of QRICH2 in spermatozoa.A novel homozygous missense variant(c.4618C>T)in QRICH2 was identified in the affected patients.Morphological analysis of spermatozoa revealed the MMAF phenotype in infertile patients.qPCR revealed a significant reduction in the level of sperm QRICH2 mRNA,and immunofluorescence staining revealed a lack of sperm QRICH2 expression.Additionally,patients harboring a homozygous QRICH2 mutation presented reduced expression of outer dense fiber 2(ODF2)in sperm,whereas sperm expression of A-kinase anchor protein 4(AKAP4)was normal.These findings expand our understanding of the genetic causes of MMAF-associated male infertility and emphasize the importance of genetic counseling.
基金supported by the National Natural Science Foundation of China(82071709,81971446,82171599,82374212)Global Select Project(DJK-LX-2022010)of the Institute of Health and Medicine,Hefei Comprehensive National Science CenterJoint Fund for New Medicine of USTC(YD9100002034)。
文摘The structural integrity of the sperm flagellum is essential for proper sperm function.Flagellar defects can result in male infertility,yet the precise mechanisms underlying this relationship are not fully understood.CCDC181,a coiled-coil domain-containing protein,is known to localize on sperm flagella and at the basal regions of motile cilia.Despite this knowledge,the specific functions of CCDC181 in flagellum biogenesis remain unclear.In this study,Ccdc181 knockout mice were generated.The absence of CCDC181 led to defective sperm head shaping and flagellum formation.Furthermore,the Ccdc181 knockout mice exhibited extremely low sperm counts,grossly aberrant sperm morphologies,markedly diminished sperm motility,and typical multiple morphological abnormalities of the flagella(MMAF).Additionally,an interaction between CCDC181 and the MMAF-related protein LRRC46 was identified,with CCDC181 regulating the localization of LRRC46 within sperm flagella.These findings suggest that CCDC181 plays a crucial role in both manchette formation and sperm flagellum biogenesis.
基金supported by the National Key Research and Development Program of China(2021YFC2701400)the National Natural Science Foundation of China(32000393,32322017,32288101)。
文摘Cytosine base editing achieves C·G-to-T·A substitutions and can convert four codons(CAA/CAG/CGA/TGG)into STOP-codons(induction of STOP-codons,iSTOP)to knock out genes with reduced mosaicism.iSTOP enables direct phenotyping in founders’somatic cells,but it remains unknown whether this works in founders’germ cells so as to rapidly reveal novel genes for fertility.Here,we initially establish that iSTOP in mouse zygotes enables functional characterization of known genes in founders’germ cells:Cfap43-iSTOP male founders manifest expected sperm features resembling human“multiple morphological abnormalities of the flagella”syndrome(i.e.,MMAF-like features),while oocytes of Zp3-iSTOP female founders have no zona pellucida.We further illustrate iSTOP’s utility for dissecting the functions of unknown genes with Ccdc183,observing MMAF-like features and male infertility in Ccdc183-iSTOP founders,phenotypes concordant with those of Ccdc183-KO offspring.We ultimately establish that CCDC183 is essential for sperm morphogenesis through regulating the assembly of outer dynein arms and participating in the intra-flagellar transport.Our study demonstrates iSTOP as an efficient tool for direct reproductive disease modeling and phenotyping in germ cells of the founder generation,and rapidly reveals the essentiality of Ccdc183 in fertility,thus providing a time-saving approach for validating genetic defects(like nonsense mutations)for human infertility.
基金supported by the National Key Research and Development Program of China(2021YFC2701400)in part by the National Natural Science Foundation of China(32000393 and 32288101).
文摘During spermiogenesis,haploid spermatids undergo dramatic morphological changes to form slender sperm flagella and cap-like acrosomes,which are required for successful fertilization.Severe deformities in flagella cause a male infertility syndrome,multiple morphological abnormalities of the flagella(MMAF),while acrosomal hypoplasia in some cases leads to sub-optimal embryonic developmental potential.However,evidence regarding the occurrence of acrosomal hypoplasia in MMAF is limited.Here,we report the generation of base-edited mice knocked out for coiled-coil domain-containing 38(Ccdc38)via inducing a nonsense mutation and find that the males are infertile.The Ccdc38-KO sperm display acrosomal hypoplasia and typical MMAF phenotypes.We find that the acrosomal membrane is loosely anchored to the nucleus and fibrous sheaths are disorganized in Ccdc38-KO sperm.Further analyses reveal that Ccdc38 knockout causes a decreased level of TEKT3,a protein associated with acrosome biogenesis,in testes and an aberrant distribution of TEKT3 in sperm.We finally show that intracytoplasmic sperm injection overcomes Ccdc38-related infertility.Our study thus reveals a previously unknown role for CCDC38 in acrosome biogenesis and provides additional evidence for the occurrence of acrosomal hypoplasia in MMAF.
基金supported by the Health Commission of Hubei Province Scientific Research Project(WJ2021M110)the National Key Research and Development Project(2018YFC1002103).
文摘This study aimed to identify genetic causes responsible for multiple morphological abnormalities of the sperm flagella(MMAF)in the Han Chinese population.Three primary infertile males with completely immobile sperm and MMAF were enrolled.Whole-exome sequencing and Sanger sequencing were performed to identify disease-causing genes.Subsequently,morphological and ultrastructural analyses of sperm flagella were investigated.The probable impact of genetic variants on protein function was analyzed by online bioinformatic tools and immunofluorescence assay.Three patients with dynein axonemal heavy chain 1(DNAH1)gene compound heterozygous variations were identified.DNAH1 c.7435C>T,p.R2479X and c.10757T>C,p.F3586S were identified in the patient from Family 1,c.11726_11727delCT,p.P3909fs and c.12154delC,p.L4052fs were found in the patient from Family 2,and c.10627-3C>G and c.11726_11727delCT,p.P3909fs existed in the patient from Family 3.Four of these variations have not been reported,and all the mutations showed pathogenicity by functional effect predictions.The absence of the center pair and disorganization of the fibrous sheath were present in sperm flagella at the ultrastructural level.Moreover,the expression of DNAH1 was absent in spermatozoa from the participants,validating the pathogenicity of the variants.All three couples have undergone intracytoplasmic sperm injection(ICSI),and two couples of them became pregnant after the treatment.In conclusion,the newly identified DNAH1 mutations can expand the mutational and phenotypic spectrum of MMAF genes and provide a theoretical basis for genetic diagnosis in MMAF patients.It is recommended to conduct genetic screening in male infertility patients with MMAF and provide rational genetic counseling,and ICSI might be an optimal strategy to help with fertilization and conception for patients with DNAH1 mutations.
基金We thank Zhang Jie for her assistance in confocal analysis(Advanced Medical Research Institute,Shandong University).This work was supported by the National Key Research and Development Programs of China(2018YFC1003400)the Young Scholars Program of Shandong University(2016WLJH50)the Natural Science Foundation of Shandong Province(ZR2017MH049).
文摘Impaired flagellar development and impaired motility of sperm is a cause of infertility in males. Several genes, including those of the AKAP, CCDC, CFAP, and DNAH families, among others, are involved in the‘‘multiple morphological abnormalities of the flagella"(MMAF) phenotype;these are the most common causes of male infertility. The Cilia-and flagella-associated protein(CFAP) family includes six members reported to cause MMAF phenotypes: CFAP43, CFAP44, CFAP69, CFAP65, CFAP70, and CFAP251. Here, we found that cilia-and flagella-associated protein 61(Cfap61) is highly expressed specifically in murine testes and show that the Cfap61-knockout male mice demonstrate MMAF phenotype, including sperm with short, coiled, and irregular flagella. Deletion of Cfap61 resulted in severe morphological and behavior abnormalities in sperm, reduced total sperm counts, impaired sperm motility, and led to male infertility.Notably, absence of Cfap61 impaired sperm flagella ultrastructural abnormalities on account of numerous distortions in multiple flagellum components. Immunostaining experiments in wild-type mice and healthy adult humans indicated that Cfap61 is initially localized at the neck of sperm, where it potentially functions in flagellum formation, and is later localized to the midpiece of the sperm. Thus, our study provides compelling evidence that dysregulation of Cfap61 affects sperm flagellum development and induces male infertility in mice. Further investigations of the CFAP61 gene in humans alongside clinical evidence showing MMAF phenotype in humans should contribute to our understanding of developmental processes underlying sperm flagellum formation and the pathogenic mechanisms that cause male infertility.
