Identification of over 500 epigenetic regulators in humans raises an interesting question regarding how chromatin dysregulation contributes to different diseases. Bromodomain and PHD finger-containing protein 1 (BRPF1) is a multivalent chromatin regulator possessing three histone-binding domains, one non-specific DNA-binding module, and several motifs for interacting with and activating three lysine acetyltransferases. Genetic analyses of fish brpf1 and mouse Brpf1 have uncovered an important role in skeletal, hematopoietic, and brain development, but it remains unclear how BRPF1 is linked to human development and disease. Here, we describe an intellectual disability disorder in ten individuals with inherited or de novo monoallelic BRPF1 mutations. Symptoms include infantile hypotonia, global developmental delay, intellectual disability, expressive language impairment, and facial dysmorphisms. Central nervous system and spinal abnormalities are also seen in some individuals. These clinical features overlap with but are not identical to those reported for persons with KAT6A or KAT6B mutations, suggesting that BRPF1 targets these two acetyltransferases and additional partners in humans. Functional assays showed that the resulting BRPF1 variants are pathogenic and impair acetylation of histone H3 at lysine 23, an abundant but poorly characterized epigenetic mark. We also found a similar deficiency in different lines of Brpf1-knockout mice. These data indicate that aberrations in the chromatin regulator gene BRPF1 cause histone H3 acetylation deficiency and a previously unrecognized intellectual disability syndrome.

Fibronectin is a master organizer of extracellular matrices (ECMs) and promotes the assembly of collagens, fibrillin-1, and other proteins. It is also known to play roles in skeletal tissues through its secretion by osteoblasts, chondrocytes, and mesenchymal cells. Spondylometaphyseal dysplasias (SMDs) comprise a diverse group of skeletal dysplasias and often manifest as short stature, growth-plate irregularities, and vertebral anomalies, such as scoliosis. By comparing the exomes of individuals with SMD with the radiographic appearance of ''corner fractures'' at metaphyses, we identified three individuals with fibronectin (FN1) variants affecting highly conserved residues. Furthermore, using matching tools and the SkelDys emailing list, we identified other individuals with de novo FN1 variants and a similar phenotype. The severe scoliosis in most individuals and rare developmental coxa vara distinguish individuals with FN1 mutations from those with classical Sutcliffe-type SMD. To study functional consequences of these FN1 mutations on the protein level, we introduced three disease-associated missense variants (p.Cys87Phe [c.260G>T], p.Tyr240Asp [c.718T>G], and p.Cys260Gly [c.778T>G]) into a recombinant secreted N-terminal 70 kDa fragment (rF70K) and the full-length fibronectin (rFN). The wild-type rF70K and rFN were secreted into the culture medium, whereas all mutant proteins were either not secreted or secreted at significantly lower amounts. Immunofluorescence analysis demonstrated increased intracellular retention of the mutant proteins. In summary, FN1 mutations that cause defective fibronectin secretion are found in SMD, and we thus provide additional evidence for a critical function of fibronectin in cartilage and bone.

No abstract

Problem The Staphylococcus aureus has been found to be associated with clinical endometritis of cow. The result of oral antibiotic remains poor. Therefore, this study investigates the role of nisin in endometritis. Method of study The effect of nisin on the growth and cell wall of S aureus were determined in vitro. Besides the blank control group, animals with established post‐partum were inoculated with 0.1 mL S aureus intravaginally. Two days post‐inoculation, the animals were administered nisin (25 mg/kg), kanamycin (30 mg/kg), and water (model group) for 7 days. On the seventh day, serum and uterine organs were obtained for pro‐ and anti‐inflammatory analysis. The uterine tissue samples were weighed, and histopathological analysis was performed. Results The results showed that nisin had an inhibitory effect on the growth and cell wall formation of S aureus. Nisin and kanamycin treatment prevented a S aureus‐induced decrease in pro‐inflammatory cytokines and promoted an increase in the level of serum anti‐inflammatory cytokines in the endometrium of these animals. Nisin and kanamycin, significantly decreased (P < 0.05) the endometritis‐induced increases in uterine weight, restored endometrial architecture and significantly (P < 0.05) normalized uterine neutrophils to control levels. Additionally, improved levels of B7‐2, IFN‐γ, IL‐2, and IL‐8 were observed when treated with nisin. Conclusion Our findings suggest that nisin compared favorably with kanamycin in endometritis prevention, suggesting that nisin can be used in S aureus‐induced endometritis by protecting the uterus from S aureus infection.