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Background Obesity is a worldwide crisis impairing human health. In this condition, declines in sperm quality stem from reductions in sperm concentration, motility and increase in sperm deformity. The mechanism underlying these alterations remains largely unknown. This study, determined if obesity-associated proteomic expression patterns in mice sperm parallel those in spermatozoa obtained from obese humans. Methods An obese mouse model was established via feeding a high-fat diet (HFD). Histological analysis identified testicular morphology and a computer assisted semen analyzer (CASA) evaluated sperm parameters. Proteome analysis was performed using a label-free quantitative LC-MS/MS system. Western blot, immunohistochemical and immunofluorescent analyses characterized protein expression levels and localization in testis, sperm and clinical samples. Results Bodyweight gains on the HFD induced hepatic steatosis. Declines in sperm motility accompanied sperm deformity development. Differential proteomic analysis identified reduced cytoskeletal proteins, centrosome and spindle pole associated protein 1 (CSPP1) and Centrin 1 (CETN1), in sperm from obese mice. In normal weight mice, both CSPP1 and CETN1 were localized in the spermatocytes and spermatids. Their expression was appreciable in the post-acrosomal region parallel to the microtubule tracks of the manchette structure in spermatids, which affects spermatid head shaping and morphological maintenance. Moreover, CSPP1 was localized in the head–tail coupling apparatus of the mature sperm, while CETN1 expression was delimited to the post-acrosomal region within the sperm head. Importantly, sperm CSPP1 and CETN1 abundance in both the overweight and obese males decreased in comparison with that in normal weight men. Conclusion These findings show that regionally distinct expression and localization of CETN1 and CSPP1 is strongly related to spermiogenesis and sperm morphology maintaining. Obesity is associated with declines in the CETN1 and CSPP1 abundance and compromise of both sperm morphology in mice and relevant clinical samples. This parallelism between altered protein expression in mice and humans suggests that these effects may contribute to poor sperm quality including increased deformity.

Summary CEP104 is an evolutionarily conserved centrosomal and ciliary tip protein. CEP104 loss-of-function mutations are reported in patients with Joubert syndrome, but their function in the etiology of ciliopathies is poorly understood. Here, we show that cep104 silencing in zebrafish causes cilia-related manifestations: shortened cilia in Kupffer’s vesicle, heart laterality, and cranial nerve development defects. We show that another Joubert syndrome-associated cilia tip protein, CSPP1, interacts with CEP104 at microtubules for the regulation of axoneme length. We demonstrate in human telomerase reverse transcriptase-immortalized retinal pigmented epithelium (hTERT-RPE1) cells that ciliary translocation of Smoothened in response to Hedgehog pathway stimulation is both CEP104 and CSPP1 dependent. However, CEP104 is not required for the ciliary recruitment of CSPP1, indicating that an intra-ciliary CEP104-CSPP1 complex controls axoneme length and Hedgehog signaling competence. Our in vivo and in vitro analyses of CEP104 define its interaction with CSPP1 as a requirement for the formation of Hedgehog signaling-competent cilia, defects that underlie Joubert syndrome., Graphical Abstract, Highlights • cep104-depleted zebrafish display shortened KV cilia and defective brain development • CEP104 interacts with CSPP1 at the tip of the primary cilium to regulate cilia length • CEP104 or CSPP1 loss in human cells leads to defective Hedgehog signaling • Impaired signaling is linked to reduction of ciliary SMO but not ARL13B or INPP5E, Deleterious mutations in CEP104 or CSPP1 cause Joubert syndrome, a ciliopathy causing an underdeveloped mid- and/or hindbrain. Frikstad et al. show that loss of cep104 in zebrafish leads to defective brain development and that CEP104 interacts with CSPP1 at the tip of the primary cilium to regulate axoneme length and Hedgehog signaling competence.

Background Recently, thousands of circular RNAs (circRNAs) have been discovered in various tissues and cell types from human, mouse, fruit fly and nematodes. However, expression of circRNAs across mammalian brain development has never been examined. Results Here we profile the expression of circRNA in five brain tissues at up to six time-points during fetal porcine development, constituting the first report of circRNA in the brain development of a large animal. An unbiased analysis reveals a highly complex regulation pattern of thousands of circular RNAs, with a distinct spatio-temporal expression profile. The amount and complexity of circRNA expression was most pronounced in cortex at day 60 of gestation. At this time-point we find 4634 unique circRNAs expressed from 2195 genes out of a total of 13,854 expressed genes. Approximately 20 % of the porcine splice sites involved in circRNA production are functionally conserved between mouse and human. Furthermore, we observe that “hot-spot” genes produce multiple circRNA isoforms, which are often differentially expressed across porcine brain development. A global comparison of porcine circRNAs reveals that introns flanking circularized exons are longer than average and more frequently contain proximal complementary SINEs, which potentially can facilitate base pairing between the flanking introns. Finally, we report the first use of RNase R treatment in combination with in situ hybridization to show dynamic subcellular localization of circRNA during development. Conclusions These data demonstrate that circRNAs are highly abundant and dynamically expressed in a spatio-temporal manner in porcine fetal brain, suggesting important functions during mammalian brain development. Electronic supplementary material The online version of this article (doi:10.1186/s13059-015-0801-3) contains supplementary material, which is available to authorized users.

Background: The multi-exon CSPP1 gene, encoding for centrosome and microtubule-associated proteins involved in ciliogenesis and cell division, is a candidate oncogene in luminal breast cancer but expression of CSPP1 proteins remained unexplored. Methods: CSPP1 gene and protein expression was examined in normal mammary tissue, human breast cancer cell lines, and primary breast cancer biopsies from two patient cohorts. Cell type and epitope-dependent subcellular-specific CSPP1 staining pattern in normal mammary gland epithelium and cancer biopsies were correlated to molecular and clinical parameters. Results: A novel, nuclear localised CSPP1 isoform was exclusively detected in luminal epithelial cells, whereas cytoplasmic CSPP-L was generally expressed in normal mammary epithelium. Luminal cell-related nuclear CSPP1 expression was preserved in type-matched cell lines and carcinomas, and correlated to gene copy number and mRNA expression. In contrast, basal-like carcinomas displayed generally lower CSPP1 mRNA expression. Yet, a subgroup of basal-like breast carcinomas depicted nuclear CSPP1 expression, displayed luminal traits, and differed from nuclear CSPP1 devoid counterparts in expression of eight genes. Eight-gene signature defined groups of basal-like tumours from an independent cohort showed significant differences in survival. Conclusions: Differential expression of a nuclear CSPP1 isoform identified biologically and clinically distinct subgroups of basal-like breast carcinoma.

Background Cerebellar vermis hypoplasia has been associated with a large number of chromosomal abnormalities and metabolic disorders, with few candidate genes clearly linked to isolated cerebellar vermis hypoplasia. Patient Description We describe on a 12-year-old boy with inferior vermian hypoplasia associated with a novel de novo microdeletion. He presented with intellectual, speech and language impairment, unilateral facial nerve weakness, marked constipation, and bilateral hand and foot anomalies that were not consistent with any previously described syndrome. His hand features were digital reductions similar to those seen in 4q34 deletion syndrome, known as the "tale of the nail" sign. Cranial magnetic resonance imaging demonstrated isolated inferior cerebellar vermis hypoplasia. Results A de novo 1.4 Mb interstitial deletion was identified at 8q13.1-q13.2 on chromosomal microarray. This copy number variant involves 18 human genome reference sequence genes, with 11 Mendelian Inheritance in Man genes. Homozygous mutations in one of these genes (CSPP1) has recently been recently described as causing Joubert syndrome. Conclusion We propose that the constellation of clinical features in this child represents a novel microdeletion syndrome and hypothesize that CSPP1 or other genes within the deleted region contribute to the cerebellar development. usc Refereed/Peer-reviewed