Objective: The kisspeptin/GPR54 pathway has been proven to be crucial in the process of puberty onset, yet the polymorphisms in the KISS1 gene and their relationships with central precocious puberty (CPP) have not been investigated. This study was performed to reveal the relationship between the gene and the disease. Design and Methods: 272 Chinese Han girls diagnosed to be CPP patients were recruited as Case Group I, 43 unrelated African women as Case Group II, and 288 unrelated normal Chinese Han girls as Control Group. Polymorphism scans of the KISS1 gene were performed for the first time by bidirectional resequencing of the whole gene in a subset of the patients, and then by ligase detection reaction some of the polymorphisms identified were typed in the two groups and the respective haplotypes were constructed. The relationships of the typed polymorphisms and the haplotypes with CPP were evaluated by an association study between genotypes and phenotypes. Results: By resequencing, eight polymorphisms were identified, five of which were typed forming 18 haplotypes. Although one novel nonsynonymous single nucleotide polymorphism substituting one amino acid in kisspeptin (P110T) was found to be statistically related to the disease (P = 0.025), no further supporting evidence has yet been found. The other polymorphisms and all the haplotypes were not found to be related. Conclusion: The polymorphism scanning and typing of KISS1 uncovered several potentially meaningful polymorphisms, but the conclusion was not solid and further studies are necessary for function validation of these polymorphisms.

In addition to the canonical role in protein homeostasis, autophagy has recently been found to be involved in axonal dystrophy and neurodegeneration. Whether autophagy may also be involved in neural development remains largely unclear. Here we report that Mir505-3p is a crucial regulator for axonal elongation and branching in vitro and in vivo, through modulating autophagy in neurons. We identify that the key target gene of Mir505-3p in neurons is Atg12, encoding ATG12 (autophagy-related 12) which is an essential component of the autophagy machinery during the initiation and expansion steps of autophagosome formation. Importantly, axonal development is compromised in brains of mir505 knockout mice, in which autophagy signaling and formation of autophagosomes are consistently enhanced. These results define Mir505-3p-ATG12 as a vital signaling cascade for axonal development via the autophagy pathway, further suggesting the critical role of autophagy in neural development.

Spiders often produce multiple types of silk, each with unique properties suiting them to certain tasks and biological functions. Orb-weaver spiders can generate more than six types of silk fibroins, with pyriform silk used to form attachment discs, adhering silk to other surfaces and substances. The unique higher-order structuring of silk fibroins has been cited as the source of their remarkable biomechanical properties. Even so, only one full-length gene sequence of pyriform silk protein 1 (PySp1) from Argiopeargentata has been reported, and studies on the mechanical properties of natural pyriform silk fibers are also lacking. To better understand the PySp1 family of genes, we used long-distance PCR (LD-PCR) to determine the sequence of PySp1 in the Araneusventricosus species. This full-length PySp1 gene is 11,931 bp in length, encoding for 3976 amino acids residues in non-repetitive N- and C-terminal domains with a central largely repetitive region made up of sixteen remarkably homogeneous units. This was similar to the previously reported A. argentata PySp1 sequence, with PySp1 from A. ventricosus also having a long repetitive N-linker that bridges the N-terminal and repetitive regions. Predictions of secondary structure and hydrophobicity of A. ventricosus PySp1 showed the pyriform silk fiber’s functional properties. The amino acid compositions of PySp1 is obviously distinct from other spidroins. Our sequence makes an important contribution to understand pyriform silk protein structure and also provides a new template for recombinant pyriform silk proteins with attractive properties.

The timing of puberty is a complex trait which is regulated by environmental and genetic factors, but the detailed regulatory mechanism remains elusive. Maternal nutrition administration during late gestation in rats revealed that the time of onset of puberty in daughter rats was influenced by the mother’s nutritional and physiological status during the embryonic development period. In this study, the potential effects of the maternal nuclear genome on the timing of puberty of offspring were investigated. Two inbred strains of mice (C3H/HeJ (C3H) and C57BL/6J (B6)) were used to set up two pedigrees (direct and reciprocal crosses), and the timing of puberty in all these mice (parent, F1 and F2) was recorded (the females were assessed by vaginal opening (VO) and the males by balano preputial separation (BPS)). The results from data of 822 mice showed that: 1) in female mice, the heritability of the timing of puberty in direct and reciprocal crosses is 68.51% and 63.97% respectively; 2) in female mice, a significant difference in the timing of puberty is observed between B6 and C3H (P = 3.7 × 10⁻¹³) mice as well as between direct and reciprocal F1 hybrids (P = 5.4 × 10⁻³), but not between direct and reciprocal F2 hybrids (P = 0.0941); 3) in male mice, direct and reciprocal F1 hybrids differ significantly from each other in the timing of BPS (P = 2.7 × 10⁻⁷), while such differences vanish in their male progenitor and progeny. The significant discrepancy between direct and reciprocal crosses in F1 but not in either cross of F2 hybrids reveals that the maternal nuclear genome has effects on the timing of puberty in mice progeny, probably through imprinting genes or the genes associated with intra-uterine physiological status.

MicroRNAs are widely referred to as gene expression regulators for different diseases. The integration between single nucleotide polymorphisms (SNPs) and miRNAs has been associated with both human and animal diseases. In order to gain new insights on the effects of SNPs on miRNA and their related sequences, we steadily characterized a whole mouse genome miRNA related SNPs, analyzed their effects on the miRNA structural stability and target alteration. In this study, we collected 73643859 SNPs across the mouse genome, analyzed 1187 pre-miRNAs and 2027 mature miRNAs. Upon mapping the SNPs, 1700 of them were identified in 702 pre-miRNAs and 609 SNPs in mature miRNAs. We also discovered that SNP densities of the pre-miRNA and mature miRNAs are lower than the adjacent flanking regions. Also the flanking regions far away from miRNAs appeared to have higher SNP density. In addition, we also found that transitions were more frequent than transversions in miRNAs. Notably, 841 SNPs could change their corresponding miRNA’s secondary structure from stable to unstable. We also performed target gain and loss analysis of 163 miRNAs and our results showed that few miRNAs remained unchanged and many miRNAs from wild mice gained target site. These results outline the first case of SNP variations in the mouse whole genome scale. Those miRNAs with changes in structure or target could be of interest for further studies.