Biallelic mutations in spermatogenesis and centriole-associated 1 like (SPATC1L) cause acephalic spermatozoa syndrome and male infertility / 亚洲男科学杂志(英文版)

Acephalic spermatozoa syndrome is a rare type of teratozoospermia that severely impairs the reproductive ability of male patients, and genetic defects have been recognized as the main cause of acephalic spermatozoa syndrome. Spermatogenesis and centriole-associated 1 like (SPATC1L) is indispensable for maintaining the integrity of sperm head-to-tail connections in mice, but its roles in human sperm and early embryonic development remain largely unknown. Herein, we conducted whole-exome sequencing (WES) of 22 infertile men with acephalic spermatozoa syndrome. An in silico analysis of the candidate variants was conducted, and WES data analysis was performed using another cohort consisting of 34 patients with acephalic spermatozoa syndrome and 25 control subjects with proven fertility. We identified biallelic mutations in SPATC1L (c.910C>T:p.Arg304Cys and c.994G>T:p.Glu332X) from a patient whose sperm displayed complete acephalia. Both SPATC1L variants are rare and deleterious. SPATC1L is mainly expressed at the head-tail junction of elongating spermatids. Plasmids containing pathogenic variants decreased the level of SPATC1L in vitro. Moreover, none of the patient's four attempts at intracytoplasmic sperm injection (ICSI) resulted in a transplantable embryo, which suggests that SPATC1L defects might affect early embryonic development. In conclusion, this study provides the first identification of SPATC1L as a novel gene for human acephalic spermatozoa syndrome. Furthermore, WES might be applied for patients with acephalic spermatozoa syndrome who exhibit reiterative ICSI failures.

The parental origin correlates with the karyotype of human embryos developing from tripronuclear zygotes / 대한생식의학회지

OBJECTIVE: It has previously been suggested that embryos developing from intracytoplasmic sperm-injected (ICSI) zygotes with three pronuclei (3PN) are endowed with a mechanism for self-correction of triploidy to diploidy. 3PN are also observed in zygotes after conventional in vitro fertilization (IVF). The parental origin, however, differs between the two fertilization methods. Whereas the vast majority of 3PN IVF zygotes are of dispermic origin and thus more likely to have two centrioles, the 3PN ICSI zygotes are digynic in origin and therefore, more likely to have one centriole. In the present study, we examine whether the parental origin of 3PN embryos correlates with the karyotype. METHODS: The karyotype of each nucleus was estimated using four sequential fluorescence in situ hybridizations-each with two probes-resulting in quantitative information of 8 different chromosomes. The karyotypes were then compared and correlated to the parental origin. RESULTS: 3PN ICSI embryos displayed a significantly larger and more coordinated reduction from the assumed initial 3 sets of chromosomes than 3PN IVF embryos. CONCLUSION: The differences in the parental origin-and hence the number of centrioles-between the 3PN IVF and the 3PN ICSI zygotes are likely to be the cause of the differences in karyotypes.

Determination of Mother Centriole Maturation in CPAP-Depleted Cells Using the Ninein Antibody

BACKGROUND: Mutations in centrosomal protein genes have been identified in a number of genetic diseases in brain development, including microcephaly. Centrosomal P4.1-associated protein (CPAP) is one of the causal genes implicated in primary microcephaly. We previously proposed that CPAP is essential for mother centriole maturation during mitosis. METHODS: We immunostained CPAP-depleted cells using the ninein antibody, which selectively detects subdistal appendages in mature mother centrioles. RESULTS: Ninein signals were significantly impaired in CPAP-depleted cells. CONCLUSION: The results suggest that CPAP is required for mother centriole maturation in mammalian cells. The selective absence of centriolar appendages in young mother centrioles may be responsible for asymmetric spindle pole formation in CPAP-depleted cells.

A Case of Small Cell Lung Carcinoma with Coexisting Autoantibodies against Proliferating Cell Nuclear Antigen and Centriole Detected Using the Autoimmune Target Test

Approximately 60-70% of small cell lung carcinoma (SCLC) cases are diagnosed at extensive stage, thus tumor markers for its early detection are needed. Autoantibodies associated with malignancy are present before radiographic detection. Autoantibodies detected using the autoimmune target (AIT) test in patients with some tumors have shown the possibility of autoantibodies to be used as a tumor marker. To overcome the limitations of antinuclear antibody (ANA) test using HEp-2 cell line, the AIT test was developed using human macrophage cell line, IT-1, as a substrate, which showed positive identification of various autoantibodies with a higher level of sensitivity. We report a case of SCLC with autoantibodies against proliferating cell nuclear antigen (PCNA) and centriole in a 70-yr-old man who had a history of heavy alcohol consumption and a 50 pack-yr history of smoking. Results of computed tomography of the chest and abdomen showed a lung mass and multiple metastases. Extensive stage SCLC was confirmed using sputum cytology and lymph node aspiration biopsy. Anti-PCNA (1:1,280) and anti-centriolar (1:320) patterns were detected using the AIT test. Neuron-specific enolase was elevated (38.2 ng/mL). There was no evidence of systemic autoimmune rheumatic disease or chronic hepatitis. This is the first case report in which coexisting autoantibodies against PCNA and centriole associated with SCLC were detected using the AIT test. This case provides some evidence that autoantibodies may be used as a tumor marker for SCLC.

Protein detection in spermatids and spermatozoa of the butterfly Euptoieta hegesia (Lepidoptera)

This study was undertaken to detect protein components in both sperm types of the butterfly Euptoieta hegesia. These spermatozoa possess complex extracellular structures for which the composition and functional significance are still unclear. In the apyrene sperm head, the proteic cap presented an external ring and an internal dense content; basic proteins were detected only in external portions. In the tail, the paracrystalline core of mitochondrial derivatives and the axoneme are rich in proteins. The extratesticular spermatozoa are covered by a proteic coat, which presented two distinct layers. In eupyrene spermatozoa, acrosome and nucleus were negatively stained, probably because of their high compaction. In the tail, there is no paracrystalline core and the axoneme presented a very specific reaction for basic proteins. The lacinate and reticular appendages are composed of cylindrical sub-units and presented a light reaction to E-PTA and a strong reaction to tannic acid. A complex proteic coat also covers the extratesticular spermatozoa. We found similarities between both extratesticular coats, indicating a possible common origin. Both spermatozoon types are rich in proteins, especially the eupyrene appendages and the extratesticular coats. We believe that both coats are related to the sperm maturation and capacitation processes.

A Study on Ciliogenesis of Tracheal Epithelium in Human Fetus / 대한해부학회지

Ciliogenesis was investigated in the tracheal epithelium of human fetus at mid trimester of gestation (15~22 weeks), and the substructure of basal body was studied with serial, cross sections. The ciliogenic cells were long columnar cells with an electron -lucent cytoplasm, and contained rich free ribosomes and smooth endoplasmic reticulum. Apical cytoplasm of these cells contained various structures related to ciliogenesis including fibrous granules, procentrioles, centrioles and basal bodies. Basal bodies were located near apical plasma membrane and had basal foot and striated rootlets. In cross section, alar sheets appeared at transitional area between distal portion of basal body and axoneme, and basal foot at distal portion of basal body. Alar sheets arouse from each peripheral triplets of basal body and projected radially clockwise in apex to base view. Basal foot was a cone shaped structure with cross striation which base attached to two or three of the peripheral triplet sets and apex converged to basal foot cap. Three dimentional reconstruction by serial cross section of the basal body showed a structural relationship of alar sheets and basal feet with basal body. By immunohistochemistry, alpha -tubulin label was seen in both basal and surface ciliated cells, and gamma-tubulin label was seen in the apical region of surface cilated cells. These results indicate that ciliogenesis of tracheal epithelium of human fetus is performed mainly by acentriolar ciliogenesis, and suggest the ciliogenesis and ciliary movement at mid trimester of gestation are active.

Immunohistochemical and Electron Microscopic Study on the Esohageal Epithelium of the Human Fetus / 체질인류학회지

To clarify the developmental characteristics of fetal esophageal epithelium especially ciliated cell, expressions of epidermal growth factor receptor (EGFR) and cytokeratin (CK) in fetal esophageal mucosa (16-24 weeks of gestation) were studied immunohistochemically, and ultrastructure of the ciliated cells was also observed. The expressions of EGFR and CK were identified in labelled streptoavidine biotin immunohistochemical method. Primary antibodies used were EGFR (Ab-4) which is affinity-purified from hyperimmune rabbit sera (Oncogene Science) and monoclonal mouse anti-human cytokeratin (DAK0-CK, MNFl16). The esophageal lumen was lined with stratified ciliated columnar epithelium between 16 and 24 weeks of gestation. The pattern of expression Of EGFR was different with gestational age and epithelial layer. The ciliated cell exhibited variable staining intensity for EGFR at 16 weeks. Some were stained intensively, and others were stained faintly. Number of ciliated cells stained intensively were gradually increased, and most of them were strongly stained at 24 weeks. The superficial non-ciliated cells, however, showed relatively constant staining property of moderate to intense between 16 and 24 weeks. EGFR immunoreactivity was minimal in the basal and intermediate cells at 16 weeks, but became more intense at 24 weeks. CK immunoreactivity in the ciliated cells between 16 and 24 weeks was similar to that of EGFR immunoreactivity. On the other hand, superficial non-ciliated cells were intense for CK staining at 16 weeks, but were very weak to negative at 24 weeks. CK immunoreactivity was intense in basal and intermediate cells between 16 and 24 weeks, but it was almost negative in the some cells of intermediate layer, especially beneath negatively stained non-ciliated cells, at 24 weeks. In electron microscopy, ciliated cells had well organized cilia and dense granules close to Golgi apparatus between 16 and 24 weeks. The cells apparently active in ciliogenesis were also observed. These cells had short microvilli, many centrioles, and dense granules close to Golgi apparatus. The non-ciliated cells contained numerous clear vesicles adluminally clustered at 16 weeks, while they had many dense vesicles of about same size of clear vesicles at 24 weeks. These results demonstrate the expressions of EGFR and CK in esophageal epithelium of human fetus between 16 and 24 weeks of gestational ages, and suggest that the ciliated cells are still proliferative at 24 weeks.

Estudo ultra-estrutural da espermatogênese de Lepidosiren paradoxa (Pisces, Dipnoi) na Amazônia / Ultrastructural study of the spermatogenesis of Lepidosiren paradoxa (Pisces, Dipnoi) in Amazonan region

Examinando o espermatozóide de Lepidosiren paradoxa (Pisces, Dipnoi) da Amazônia, através de microsocpias de luz e eletrônicas de transmissäo e varredura, observamos ser constituído de três partes: (a) cabeça, com um grande núcleo alongado; (b) peça intermediária, onde estäo incluídas mitocôndrias, dois centríolos e corpo granular retro-nuclear; (c) cauda constituída de dois flagelos bem distintos, onde se destaca a organizaçäo axonêmica do tipo 9p + 2s envolvida por uma membrana tipo ondulante