BACKGROUND: Premature ovarian insufficiency (POI) is one of the causes of female infertility. Unexplained POI is increasingly affecting women in their reproductive years. However, the etiology of POI is diverse and remains elusive. We and others have shown that brain-derived neurotrophic factor (BDNF) plays an important role in adult ovarian function. Here, we report on a novel role of BDNF in the Developmental Origins of POI.
METHODS: Placental BDNF knockout mice were created using CRISPR/CAS9. Homozygous knockout (cKO(HO)) mice didn\'t survive, while heterozygous knockout (cKO(HE)) mice did. BDNF reduction in cKO(HE) mice was confirmed via immunohistochemistry and Western blots. Ovaries were collected from cKO(HE) mice at various ages, analyzing ovarian metrics, FSH expression, and litter sizes. In one-month-old mice, oocyte numbers were assessed using super-ovulation, and oocyte gene expression was analyzed with smart RNAseq. Ovaries of P7 mice were studied with SEM, and gene expression was confirmed with RT-qPCR. Alkaline phosphatase staining at E11.5 and immunofluorescence for cyclinD1 assessed germ cell number and cell proliferation.
RESULTS: cKO(HE) mice had decreased ovarian function and litter size in adulthood. They were insensitive to ovulation induction drugs manifested by lower oocyte release after superovulation in one-month-old cKO(HE) mice. The transcriptome and SEM results indicate that mitochondria-mediated cell death or aging might occur in cKO(HE) ovaries. Decreased placental BDNF led to diminished primordial germ cell proliferation at E11.5 and ovarian reserve which may underlie POI in adulthood.
CONCLUSIONS: The current results showed decreased placental BDNF diminished primordial germ cell proliferation in female fetuses during pregnancy and POI in adulthood. Our findings can provide insights into understanding the underlying mechanisms of POI.

The early gonads of mammals contain primordial germ cells (PGCs) and somatic cell precursors that are essential for sex determination and gametogenesis. Although it is extensively documented in mice, the development of early gonads in non-rodents remains to be delineated. Because molecular differences between mouse and human gonadal cells have been reported, it warrants the study of the key markers and regulatory features that are conserved or divergent between non-rodent species and human. Here, we integrate single-cell transcriptome and chromatin accessibility analysis to identify regulatory signatures of PGCs and somatic cells in the early gonads of goats, pigs, macaques, and humans. We identify the evolutionarily conserved and species-specific events, including genes expression, signaling pathways, and cell-cell interactions. We also uncover potential cis-regulatory elements and key transcription factors in PGCs and somatic cells. Our datasets provide important resources for better understanding the evolutionary programs of PGCs and gonadal somatic cell development in mammals.

Poultry genetics resources, including commercial selected lines, indigenous breeds, and experimental lines, are now being irreversibly lost at an alarming rate due to multiple reasons, which further threats the future livelihood and academic purpose. Collections of germplasm may reduce the risk of catastrophic loss of genetic diversity by guaranteeing that a pool of genetic variability is available to ensure the reintroduction and replenishment of the genetic stocks. The setting up of biobanks for poultry is challenging because the high sensitiveness of spermatozoa to freezing-thawing process, inability to cryopreserve the egg or embryo, coupled with the females being heterogametic sex. The progress in cryobiology and biotechnologies have made possible the extension of the range of germplasm for poultry species available in cryobanks, including semen, primordial germ cells, somatic cells and gonads. In this review, we introduce the state-of-the-art technologies for avian genetic resource conservation and breed reconstruction, and discuss the potential challenges for future study and further extending of these technologies to ongoing and future conservation efforts.

Spinyhead croaker (Collichthys lucidus) is an economically important fish suffering from population decline caused by overfishing and habitat destruction. Researches on the development of primordial germ cell (PGC) and reproduction biology were an emergency for the long-term conservation of the involved species. Dead end (dnd) gene plays an indispensable role in PGC specification, maintenance, and development. In the current study, we report the cloning and expression patterns of dnd in C. lucidus (Cldnd). RT-PCR analysis revealed that Cldnd was specifically expressed in both sexual gonads. In the ovary, Cldnd RNA was uniformly distributed in the oocytes and abundant in oogonia, and gradually decreased with oogenesis. A similar expression pattern was also detected in testis. Dual fluorescent in situ hybridization of Cldnd and Clvasa demonstrated that they almost had the same distribution except in oocytes at stage I, in which the vasa RNA aggregated into some particles. Furthermore, Cldnd 3\' UTR was sufficient to guide the Green Fluorescent Protein (GFP) specifically and stably expressed in the PGCs of medaka. These findings offer insight into that Cldnd is an evolutionarily conserved germline-specific gene and even a potential candidate for PGC manipulation in C. lucidus.

Aims: We aimed to explore diagnostic efficiencies of long noncoding RNAs (lncRNAs) adjacent to PGC combining with sPGC and anti-Helicobacter pylori IgG in identifying GC (gastric cancer) and precancerous disease. Patients & methods: A total of 265 patients with different gastric diseases were collected. ELISA was to detect sPGC and anti-H. pylori IgG. LncRNAs was determined by qRT-PCR. Results: The area under receiver operating characteristic curve of lncRNAs in discriminating GC+AG (atrophic gastritis) and superficial gastritis (SG) were 79.0, 68.1 and 75.9%. The diagnostic performance of lncRNAs with sPGC had increasing trends in distinguishing GC from non-GC, SG from GC+AG comparing with lncRNAs, with no statistic difference. Diagnosis efficacies of lncRNAs with anti-H. pylori IgG improved dramatically. Conclusions: Serum lncRNAs could distinguish GC, AG and SG. Diagnosis efficiencies of lncRNAs with sPGC and anti-H. pylori-IgG could be improved.

Aerobic anoxygenic photoheterotrophic bacteria (AAPB) represent a bacteriochlorophyll a-containing functional group. Substantial evidence indicates that highly conserved photosynthetic gene clusters (PGCs) of AAPB can be transferred between species, genera, and even phyla. Furthermore, analysis of recently discovered PGCs carried by extrachromosomal replicons (exPGCs) suggests that extrachromosomal replicons (ECRs) play an important role in the transfer of PGCs. In this study, 13 Roseobacter clade genomes from seven genera that harbored exPGCs were used to analyze the characteristics and evolution of PGCs. The identification of plasmid-like and chromid-like ECRs among PGC-containing ECRs revealed two different functions: the spread of PGCs among strains and the maintenance of PGCs within genomes. Phylogenetic analyses indicated two independent origins of exPGCs, corresponding to PufC-containing and PufX-containing puf operons. Furthermore, the two different types of operons were observed within different strains of the same Tateyamaria and Jannaschia genera. The PufC-containing and PufX-containing operons were also differentially carried by chromosomes and ECRs in the strains, respectively, which provided clear evidence for ECR-mediated PGC transfer. Multiple recombination events of exPGCs were also observed, wherein the majority of exPGCs were inserted by replication modules at the same genomic positions. However, the exPGCs of the Jannaschia strains comprised superoperons without evidence of insertion and therefore likely represent an initial evolutionary stage where the PGC was translocated from chromosomes to ECRs without further combinations. Finally, a scenario of PGC gain and loss is proposed that specifically focuses on ECR-mediated exPGC transfer to explain the evolution and patchy distribution of AAPB within the Roseobacter clade.IMPORTANCE The evolution of photosynthesis was a significant event during the diversification of biological life. Aerobic anoxygenic photoheterotrophic bacteria (AAPB) share physiological characteristics with chemoheterotrophs and represent an important group associated with bacteriochlorophyll-dependent phototrophy in the environment. Here, characterization and evolutionary analyses were conducted for 13 bacterial strains that contained photosynthetic gene clusters (PGCs) carried by extrachromosomal replicons (ECRs) to shed light on the evolution of chlorophototrophy in bacteria. This report advances our understanding of the importance of ECRs in the transfer of PGCs within marine photoheterotrophic bacteria.

Autism is a childhood neuropsychiatric disorder with evidence of a strong genetic component in the complex etiologies. Contactin-associated protein-like 2 (CNTNAP2), a member of the neurexin superfamily, plays an essential role in neural development. CNTNAP2 was considered as one of the most susceptible genes for autism spectrum disorder (ASD). Some studies indicated the association of CNTNAP2 with ASD, while others reported no association. Given the inconsistent results of the previous studies, we performed a family-based association study between 9 single-nucleotide polymorphisms (SNPs) of CNTNAP2 and autism in 640 autistic trios in the Chinese Han population. Then, an updated meta-analysis, combined with the data from Psychiatric Genomics Consortium (iPSYCH-PGC ASD, 2017) and available association studies, was conducted. No SNPs were significantly associated with autism in the Chinese Han population. In the meta-analysis, the two frequently reported SNPs (rs2710102 and rs7794745) showed no significant association with ASD. Therefore, CNTNAP2 polymorphisms might not be associated with autism. Autism Research 2019, 12: 553-561. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: In present family-based association study, no single-nucleotide polymorphisms (SNPs) were significantly associated with autism in the Chinese Han population. In the updated meta-analysis, the association between the two frequently reported SNPs (rs2710102 and rs7794745) in CNTNAP2 and the risk of ASD was explored. However, the results showed no significant association. Therefore, our study suggested that CNTNAP2 polymorphisms might not be associated with autism.

Imaging genetics posits a valuable strategy for elucidating genetic influences on brain abnormalities in psychiatric disorders. However, association analysis between 2D genetic data (subject × genetic variable) and 3D first-level functional magnetic resonance imaging (fMRI) data (subject × voxel × time) has been challenging given the asymmetry in data dimension. A summary feature needs to be derived for the imaging modality to compute inter-modality association at subject level. In this work, we propose to use variability in resting state networks (RSNs) and functional network connectivity (FNC) as potential features for purpose of association analysis. We conducted a pilot study to investigate the proposed features in a dataset of 171 healthy controls and 134 patients with schizophrenia (SZ). We computed variability in RSN and FNC in a group independent component analysis framework and tested three types of variability metrics, namely Euclidean distance, Pearson correlation and Kullback-Leibler (KL) divergence. Euclidean distance and Pearson correlation metrics more effectively discriminated controls from patients than KL divergence. The group differences observed with variability in RSN and FNC were highly consistent, indicating patients presenting increased deviation from the cohort-common pattern of RSN and FNC than controls. The variability in RSN and FNC showed significant associations with network global efficiency, the more the deviation, the lower the efficiency. Furthermore, the RSN and FNC variability were found to associate with individual SZ risk SNPs as well as cumulative polygenic risk score for SZ. Collectively the current findings provide preliminary evidence for variability in RSN and FNC being promising imaging features that may find applications as biomarkers and in imaging genetic association analysis.

Cistanche is the traditional and precious Chinese herbal, with two thousand years of use history in China. It has the effect on tonifying kidney, strong supplement to the liver and kidney, and replenishing essence and blood, known as the \"desert ginseng\". Here, we explored the mechanism of Phenylethanoid Glycosides of Cistanche (PGC) to the model mice of menopausal syndrome, as well as the therapeutic effect and characteristics of PGC to the menopausal syndrome. In this study, KM mice were reproduced by the complete resection of the ovaries on both sides of the back to establish the model mice of menopausal syndrome (MPS), and received distilled water or drugs, respectively. Model mice received distilled water. Mice received 200 mg/(kg day) high doses of Phenylethanoid Glycosides of Cistanche (HPGC), and 100 mg/(kg day) medium doses of Phenylethanoid Glycosides of Cistanche (MPGC), and 50 mg/(kg day) low doses of Phenylethanoid Glycosides of Cistanche (LPGC). After 21 days, it could determine the number of independent activities and the number of standing, the latent period of first entering the dark room, and the electric number. It also calculated the viscera index of uterus, thymus, spleen, measured the levels of estradiol (E2), testosterone (T), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in the serum. Furthermore, it observed the pathological changes of uterus, thymus, spleen and pituitary of mice. The results showed that behavioral indicators: Compared with the model group (MG), HPGC, MPGC, LPGC could increase the independent activities (P < 0.01); HPGC, MPGC could increase the number of standing, the latent period of first entering the dark room, and reduce the electric number (P < 0.01); LPGC could increase the number of standing (P < 0.05); Viscera index: Compared with MG, HPGC, MPGC could increase the viscera index of uterus, thymus, spleen (P < 0.01); LPGC could increase the viscera index of uterus (P < 0.05); Serum index: Compared with MG, all groups could decrease the levels of LH in the serum (P < 0.01); HPGC, MPGC could improve the levels of E2, T and decrease the levels of LH, FSH in the serum (P < 0.01); LPGC could improve the levels of E2 and decrease the levels of FSH in the serum (P < 0.05). Meanwhile, it had the trend to improve the levels of T in the serum. Pathological changes: Compared with MG, HPGC could significant improve the pathological changes of uterus, thymus, spleen and pituitary of mice; other groups also has a certain effect. The results indicated that PGC could improve the sex hormone disorder of MPS, and restore the function of uterus, thymus and spleen, with better therapeutic effect on MPS.

Dead end (dnd), vertebrate-specific germ cell marker, had been demonstrated to be essential for primordial germ cell (PGC) migration and survival, and the link between PGC number and sex change had been revealed in some teleost species, but little is known about dnd in hermaphroditic vertebrates. In the present study, a protogynous hermaphroditic orange-spotted grouper (Epinephelus coioides) dnd homologue (Ecdnd) was identified and characterized. Quantitative real-time PCR and in situ hybridization analysis revealed a dynamic and sexually dimorphic expression pattern in PGCs and germ cells of gonads. During sex changing, the Ecdnd transcript sharply increased in early transitional gonad, reached the highest level at late transitional gonad stage, and decreased after testis maturation. Visualization of zebrafish PGCs by injecting with RFP-Ecdnd-3\'UTR RNA and GFP-zfnanos3-3\'UTR RNA confirmed importance of Ecdnd 3\'UTR for the PGC distribution. In addition, knockdown of EcDnd by using antisense morpholinos (MO) caused the ablation of PGCs in orange-spotted grouper. Therefore, the current data indicate that Ecdnd is essential for PGCs survival and may serve as a useful germ cell marker during gametogenesis in hermaphroditic grouper.