Conserved and unique amino acid residues in the domains of the growth hormones. Flounder growth hormone deduced from the cDNA sequence has the minimal size in the growth hormone prolactin gene family

Growth hormone (GH), prolactin (PRL), and placental lactogen (PL) constitute a protein family whose genes are considered to have evolved from a common ancestral gene. GHs isolated from various vertebrate species are known to possess highly conserved structural and functional features. In the present study we have cloned and sequenced flounder growth hormone (fGH) cDNA to predict the primary structure of the hormone. The preprotein of fGH is composed of 190 amino acids, and mature fGH is found to be extraordinarily small, having 171 or 173 amino acid residues. The estimated molecular masses of mature fGH are 19.4 to 19.7 kDa. This minimal size of fGH enabled an extended analysis of the essential domains and of amino acid residues required in hormone-specific activities. fGH conserves and shares 37 residues with 20 other vertebrate GHs. These common residues are seen to cluster in five distinct domains (GD1 to GD5). In human PL (hPL), which has low growth-promoting activity, 35 of these 37 residues are conserved, while the other 2 residues in the GD1 domain (Arg-16 and Leu-20) are replaced by Gln and Ala, respectively. In a less active variant of human GH, hGH-V, only 1 residue (His-21) of the 37 residues is replaced by Tyr. Besides these 3 residues, 6 other residues unique to the GHs and some PLs, that is, Ala-24 (GD1), Ser-54 (GD2), Ser-78 (GD3), Leu-106, Leu-116, and Asp-122 (GD4), appear to be important for specific binding of the GHs. The GD5 domain, at the carboxyl-terminal ends of the GHs is considered to be involved mainly in the formation and stabilization of GH molecules.     

Nox4-dependent ROS modulation by amino endoperoxides to induce apoptosis in cancer cells

Tumor metastasis is the main cause of death in cancer patients. Anoikis resistance is one critical malefactor of metastatic cancer cells to resist current clinical chemotherapeutic treatments. Although endoperoxide-containing compounds have long been suggested as anticancer drugs, few have been clinically employed due to their instability, complex synthesis procedure or low tumor cell selectivity. Herein, we describe a one-pot strategy to synthesize novel amino endoperoxides and their derivatives with good yields and stabilities. In vitro cell-based assays revealed that 4 out of the 14 amino endoperoxides selectively induce metastatic breast carcinoma cells but not normal breast cells to undergo apoptosis, in a dose-dependent manner. Mechanistic studies showed that the most potent amino endoperoxide, 4-Me, is selective for cancer cells expressing a high level of Nox4. The anticancer effects are further shown to be associated with reduced O₂⁻:H₂O₂ ratio and increased ·OH level in the cancerous cells. Animal study showed that 4-Me impairs orthotopic breast tumor growth as well as tumor cell metastasis to lymph nodes. Altogether, our study suggests that anticancer strategies that focus on redox-based apoptosis induction in tumors are clinically viable.     

Distribution of TRPVs,P2X3, and Parvalbumin in the Human Nodose Ganglion

Immunohistochemistry for several neurochemical substances, the transient receptor potential cation channel subfamily V member 1 (TRPV1) and 2 (TRPV2), P2X3 receptor, and parvalbumin (PV), was performed on the nodose ganglion, pharynx, and epiglottis in human cadavers. The nodose ganglion was situated beneath the jugular foramen, and had a spindle shape with the long rostrocaudal axis. The pharyngeal branch (PB) issued from a rostral quarter of the nodose ganglion, whereas the superior laryngeal nerve (SLN) usually originated from a caudal half of the ganglion. In the nodose ganglion, sensory neurons were mostly immunoreactive for TRPV1 (89 %) or P2X3 (93.9 %). About 30 % of nodose neurons contained TRPV2 (35.7 %)—or PV (29.9 %)—immunoreactivity (-IR). These neurons mainly had small to medium-sized cell bodies, and were distributed throughout the ganglion. Neurodegenerative profiles such as shrinkage or pyknosis could not be detected in the examined ganglion. Occasionally, TRPV2-IR nerve fibers surrounded blood vessels in the epiglottis as well as in the nasal and oral parts of the pharynx. Isolated TRPV2-IR nerve fibers were also located beneath the epithelium. TRPV1-, P2X3-, or PV-IR nerve endings could not be detected in the pharynx or epiglottis. In the PB and SLN, however, numerous nerve fibers contained TRPV1-, TRPV2-, P2X3-, and PV-IR. The present study suggests that TRPV1-, TRPV2-, P2X3-, and PV-IR neurons in the human nodose ganglion innervate the pharynx and epiglottis through the PB and SLN. These neurons may respond to chemical, thermal, and mechanical stimuli during respiration and swallowing.     

Reduced phototropism in pks mutants may be due to altered auxin‐regulated gene expression or reduced lateral auxin transport

Phototropism allows plants to orient their photosynthetic organs towards the light. In Arabidopsis, phototropins 1 and 2 sense directional blue light such that phot1 triggers phototropism in response to low fluence rates, while both phot1 and phot2 mediate this response under higher light conditions. Phototropism results from asymmetric growth in the hypocotyl elongation zone that depends on an auxin gradient across the embryonic stem. How phototropin activation leads to this growth response is still poorly understood. Members of the phytochrome kinase substrate (PKS) family may act early in this pathway, because PKS1, PKS2 and PKS4 are needed for a normal phototropic response and they associate with phot1 in vivo. Here we show that PKS proteins are needed both for phot1‐ and phot2‐mediated phototropism. The phototropic response is conditioned by the developmental asymmetry of dicotyledonous seedlings, such that there is a faster growth reorientation when cotyledons face away from the light compared with seedlings whose cotyledons face the light. The molecular basis for this developmental effect on phototropism is unknown; here we show that PKS proteins play a role at the interface between development and phototropism. Moreover, we present evidence for a role of PKS genes in hypocotyl gravi‐reorientation that is independent of photoreceptors. pks mutants have normal levels of auxin and normal polar auxin transport, however they show altered expression patterns of auxin marker genes. This situation suggests that PKS proteins are involved in auxin signaling and/or lateral auxin redistribution.     

Seahawk: moving beyond HTML in Web-based bioinformatics analysis

Background  

Traditional HTML interfaces for input to and output from Bioinformatics analysis on the Web are highly variable in style, content and data formats. Combining multiple analyses can therfore be an onerous task for biologists. Semantic Web Services allow automated discovery of conceptual links between remote data analysis servers. A shared data ontology and service discovery/execution framework is particularly attractive in Bioinformatics, where data and services are often both disparate and distributed. Instead of biologists copying, pasting and reformatting data between various Web sites, Semantic Web Service protocols such as MOBY-S hold out the promise of seamlessly integrating multi-step analysis.     

Differential expression of the auxin primary response gene MASSUGU2/IAA19during tropic responses of Arabidopsis hypocotyls

We have examined the expression pattern of an auxin primary response gene, MSG2/IAA19 , during photo- and gravitropic responses of hypocotyls using a transgenic Arabidopsis harboring MSG2/IAA19 promoter::GUS . The upper portion of most etiolated hypocotyls showed uniform β-glucuronidase (GUS) staining with the strongest activity in the pericycle. When hypocotyls were irradiated with unilateral blue light, GUS activity on the concave side of hypocotyls was decreased, resulting in differential GUS staining with a stronger signal on the convex side. The number of differentially stained hypocotyls peaked at 24 h after the onset of the phototropic stimuli, while hypocotyl curvature continued to increase for the entire 36-h experimental period. This result suggests that the MSG2/IAA19 expression precedes the phototropic responses. When seedlings were grown under dim white light, their hypocotyls displayed almost no GUS activity. The light-grown hypocotyls also showed differential GUS staining after phototropic stimuli as result of the increase in GUS activity on the convex side of hypocotyls, especially in the epidermis, the outer cortex and pericycle, although GUS activity was much weaker than that observed in etiolated hypocotyls. Similar but less obvious differential staining was obtained for gravitropic response of hypocotyls. Considering the recent finding that Aux/IAA proteins are immediate targets of the auxin F box receptors, MSG2/IAA19 is likely to act as one of master genes for tropic responses.     

Specificity and similarity of functions of the Aux/IAA genes in auxin signaling of Arabidopsis revealed by promoter-exchange experiments among MSG2/IAA19, AXR2/IAA7, and SLR/IAA14

As indicated by various and some overlapped phenotypes of the dominant mutants, the Aux/IAA genes of Arabidopsis (Arabidopsis thaliana) concomitantly exhibit a functional similarity and differentiation. To evaluate the contributions of their expression patterns determined by promoter activity and molecular properties of their gene products to Aux/IAA function, we examined phenotypes of transgenic plants expressing the green fluorescent protein (GFP)-tagged msg2-1/iaa19, axr2-1/iaa7, or slr-1/iaa14 cDNA by the MSG2 or AXR2 promoter. When driven by the MSG2 promoter (pMSG2), each GFP-tagged cDNA caused the msg2-1 phenotype, that is, the wild-type stature in the mature-plant stage, long and straight hypocotyls in the dark, reduced lateral root formation, relatively mild agravitropic traits in hypocotyls, and a normal gravitropic response in roots. However, development of one or two cotyledonary primordia was often arrested in embryogenesis of the pMSG2::axr2-1::GFP and pMSG2::slr-1::GFP plants, resulting in monocotyledonary or no cotyledonary seedlings. Such defects in embryogenesis were never seen in pMSG2::msg2-1::GFP or the msg2-1, axr2-1, or slr-1 mutant. The MSG2 promoter-GUS staining showed that expression of MSG2 started specifically in cotyledonary primordia of the triangular-stage embryos. When driven by the AXR2 promoter (pAXR2), each GFP-tagged mutant cDNA caused, in principle, aberrant aboveground phenotypes of the corresponding dominant mutant. However, either the axr2-1::GFP or slr-1::GFP cDNA brought about dwarf, agravitropic stems almost identical to those of axr2-1, and the pAXR2::msg2-1::GFP and pAXR2::slr-1::GFP hypocotyls exhibited complete loss of gravitropism as did axr2-1. These results showed functional differences among the msg2-1, axr2-1, and slr-1 proteins, though some phenotypes were determined by the promoter activity.