Monogamous mating system and sexuality in the gobiid fish, Trimma marinae (Actinopterygii: Gobiidae)

The mating system and sexuality of the gobiid fish Trimma marinae were investigated in aquaria and by gonadal histological examination. The male to female sex ratio in the study aggregation was female-biased (14:27), and females were larger than males. T. marinae were monogamous because they established continuous pairs and spawned repeatedly with the same individuals. Observations of aggressive behavior suggested that the monogamous mating system resulted from female mate guarding. We also performed a rearing experiment to test whether sex change occurs in this species. As a result, none of the males or females reared separately in aquaria for 63 days changed sex. Additionally, gonadal histology revealed that mature fish had unisexual gonads (testis or ovary). These results strongly suggest that T. marinae is gonochoristic. However, immature fish had a bisexual gonadal structure, indicating juvenile hermaphroditism

Symmetrical Skin Lesions on the Gluteal Region in a Patient with Anti-Laminin-332 Mucous Membrane Pemphigoid

Mucous membrane pemphigoid (MMP), previously called cicatricial pemphigoid, is a rare subepidermal immunobullous disorder that primarily affects the mucous membranes (1,2). MMP is divided into two major subtypes, anti-BP180-type MMP and anti-laminin-332 (previously called laminin 5 or epiligrin) MMP. Anti-laminin-332 MMP is known to be associated with malignant tumors (3), which may cause overexpression of autoantibodies and induce autoimmunity to laminin-332 (4). MMP primarily affects the mucous membranes, and widespread skin lesions are rare. In MMP, circumscribed skin lesions have been previously reported as occurring on the head, neck, and upper trunk (5). We report a case of anti-laminin-332 MMP presenting with symmetrical skin lesions characteristic of MMP on the weightbearing areas of the gluteal regio

Angle-resolved photoemission study of MX-chain compound [Ni(chxn)2_2Br]Br2_2

We report on the results of angle-resolved photoemission experiments on a quasi-one-dimensional $MX$-chain compound [Ni(chxn)$_2$Br]Br$_2$ (chxn = 1$R$,2$R$-cyclohexanediamine), a one-dimensional Heisenberg system with $S=1/2$ and $J \sim 3600$ K, which shows a gigantic non-linear optical effect. A "band" having about 500 meV energy dispersion is found in the first half of the Brillouin zone $(0\le kb/\pi <1/2)$, but disappears at $kb / \pi \sim 1/2$. Two dispersive features, expected from the spin-charge separation, as have been observed in other quasi-one-dimensional systems like Sr$_2$CuO$_3$, are not detected. These characteristic features are well reproduced by the $d$-$p$ chain model calculations with a small charge-transfer energy $\Delta$ compared with that of one-dimensional Cu-O based compounds. We propose that this smaller $\Delta$ is the origin of the absence of clear spin- and charge-separation in the photoemission spectra and strong non-linear optical effect in [Ni(chxn)$_2$Br]Br$_2$.Comment: 4 pages, 3 figure

The Constrained Maximal Expression Level Owing to Haploidy Shapes Gene Content on the Mammalian X Chromosome.

X chromosomes are unusual in many regards, not least of which is their nonrandom gene content. The causes of this bias are commonly discussed in the context of sexual antagonism and the avoidance of activity in the male germline. Here, we examine the notion that, at least in some taxa, functionally biased gene content may more profoundly be shaped by limits imposed on gene expression owing to haploid expression of the X chromosome. Notably, if the X, as in primates, is transcribed at rates comparable to the ancestral rate (per promoter) prior to the X chromosome formation, then the X is not a tolerable environment for genes with very high maximal net levels of expression, owing to transcriptional traffic jams. We test this hypothesis using The Encyclopedia of DNA Elements (ENCODE) and data from the Functional Annotation of the Mammalian Genome (FANTOM5) project. As predicted, the maximal expression of human X-linked genes is much lower than that of genes on autosomes: on average, maximal expression is three times lower on the X chromosome than on autosomes. Similarly, autosome-to-X retroposition events are associated with lower maximal expression of retrogenes on the X than seen for X-to-autosome retrogenes on autosomes. Also as expected, X-linked genes have a lesser degree of increase in gene expression than autosomal ones (compared to the human/Chimpanzee common ancestor) if highly expressed, but not if lowly expressed. The traffic jam model also explains the known lower breadth of expression for genes on the X (and the Z of birds), as genes with broad expression are, on average, those with high maximal expression. As then further predicted, highly expressed tissue-specific genes are also rare on the X and broadly expressed genes on the X tend to be lowly expressed, both indicating that the trend is shaped by the maximal expression level not the breadth of expression per se. Importantly, a limit to the maximal expression level explains biased tissue of expression profiles of X-linked genes. Tissues whose tissue-specific genes are very highly expressed (e.g., secretory tissues, tissues abundant in structural proteins) are also tissues in which gene expression is relatively rare on the X chromosome. These trends cannot be fully accounted for in terms of alternative models of biased expression. In conclusion, the notion that it is hard for genes on the Therian X to be highly expressed, owing to transcriptional traffic jams, provides a simple yet robustly supported rationale of many peculiar features of X's gene content, gene expression, and evolution

CONSERVED EXPRESSION OF SOX13 ORTHOLOGS IN EARLY VERTEBRATE DEVELOPMENT

The skin and nervous tissue is derived from the ectoderm^. In Xenopus, ectodermal explants (animal caps) from blastula embryos show high tissue plasticity and can differentiate into a variety of tissues in vitro. Exploiting this property, we performed a functional screening for factors that can neuralize ectodermal explants, and isolated Xenopus Sox13 (XSox13), a member of the Sox (Sry-related high-mobility-group box) transcription factor family. During Xenopus embryogenesis, XSox13 mRNA is expressed in the entire ectoderm at blastula stages and in the organizer region at gastrula stages. Its expression becomes localized to the neural tube during neurulation and then to somites at tailbud stages.　Mouse Sox13 mRNA shows similar expression patterns to the Xenopus homolog during embryogenesis : Sox13 is expressed in the node, an equivalent to the Xenopus organizer, at the neural fold stage, exclusively in the nervous tissue at early-mid somite stages, and then showed a segmental expression in the somites at the late somite stage. We next generated Sox13-LacZ-knock-in mice, and examined the expression of mouse Sox13 in adult tissues by X-gal staining. In contrast to the expression during embryogenesis, Sox13 is scarcely expressed in the central nervous system in adult.　Moreover, Sox13-deficient mice showed no apparent abnormalities in neural development.　These results suggest that Sox13 expression in early development is conserved in Xenopus and mouse and Sox13 plays a redundant role during mouse neural development

OVEREXPRESSION OF PROGRANULIN INCREASES CELLS IN GROWTH PHASE, BUT IS INSUFFICIENT TO INDUCE SKIN TUMOR FORMATION

Progranulin (PGRN), a multifunctional secreted growth factor, is highly expressed in various types of human cancers. However, it is still unknown whether upregulation of PGRN is a cause or a result of cancerous transformation. To assess the consequences of enhanced PGRN expression in vivo, we generated transgenic mice in which PGRN is specifically expressed in keratinocytes using the Cre/lox system. PGRN overexpression in the epidermis promoted the entry of basal cells to the proliferation phases, as revealed by Ki-67 immunostaining, but was insufficient to facilitate it to the mitotic phase, as revealed by phosphohistone H3 immunoreactivity. Accordingly, we observed no significant difference in the incidence of spontaneously occurring and chemically induced skin tumors between the transgenic and wild-type mice. These results suggest that overexpression of PGRN alone is insufficient to cause cancerous transformation of keratinocytes