Divergence of Eurosta solidaginis in response to host plant variation and natural enemies

We tested the hypothesis that forest and prairie populations of the gall-inducing fly, Eurosta solidaginis, have diverged in response to variation in selection by its host plant Solidago altissima, and its natural enemies. A reciprocal cross infection design experiment demonstrated that fly populations from the prairie and forest biomes had higher survival on local biome plants compared to foreign biome host plants. Flies from each biome also had an oviposition preference for their local plants. Each fly population induced galls of the size and shape found in their local biome on host plants from both biomes indicating a genetic basis to the differences in gall morphology. Solidago altissima from the prairie and forest biomes retained significant morphological differences in the common garden indicating that they are genetically differentiated, possibly at the subspecies level. The populations are partially reproductively isolated as a result of a combination of prezygotic isolation due to host-associated assortative mating, and postzygotic isolation due to low hybrid survival. We conclude that E. solidaginis is undergoing diversifying selection to adapt to differences between prairie and forest habitats.     

Hic‐5 affects proliferation,migration and invasion of B16 murine melanoma cells

Hic‐5 is a shuttling protein between the cell membrane and the nucleus which functions as a focal adhesion adaptor protein and a nuclear receptor coactivator. Although several studies have shown its involvement in other types of cancer, the role of Hic‐5 in melanoma is unknown. Herein, we show for the first time that Hic‐5 is expressed in B16‐F1 murine melanoma cells. To determine its function in melanoma cells, we used shRNA‐mediated RNA interference and established stable clones with down‐regulated Hic‐5 expression. These clones had impaired growth and metastatic potential compared with controls in vivo, which correlated with decreased proliferation, migration and invasion in vitro. Moreover, silencing of Hic‐5 expression in B16‐F1 activated RhoA with an amoeboid phenotypic change, indicating that Hic‐5 is a key regulator of B16‐F1 metastasis in the context of Rho‐dependent motility. These results provide new evidence that Hic‐5 is a possible molecular target for treatment of melanoma.     

Gene expression in haemocytes of kuruma prawn,Penaeus japonicus,in response to infection with WSSV by EST approach

Gene expression in haemocytes of the kuruma prawn (Penaeus japonicus) was investigated using an expressed sequence tag (EST) approach. Partial nucleotide sequences of cDNA library clones constructed from normal and white spot syndrome virus (WSSV)--infected P. japonicus haemocytes were determined. Of 635 clones obtained from the normal library, 284 (44.7%) significantly matched sequences in GenBank, and of 370 clones obtained from WSSV-infected library, 174 (47.0%) significantly matched sequences in the database. One hundred fifty-two deduced proteins were newly identified. Of these, 28 types were involved in biodefence. For the prophenoloxidase system, there are prophenoloxidase, coagulation factor G-beta chain precursor, factor D, Masquarade-like protease, transglutaminase (TGase), clottable protein and eight types of protease inhibitors (two types of antileukoproteinase, alpha-2-macroglobulin, chelonianin, elastase inhibitor, two types of Kazal inhibitor and Kunitz-type inhibitor). For antibacterial peptides, there are bactinecin 11, penaeidin-2 precursor and lysozyme c type. The others defence-related proteins are basophil leukocyte interleukin-3-regulated protein, natural killer enhancing factor (NK-EF), integral membrane protein (CD34+), ESM-1, Notch homologue and Drac homologue. For the adhesion proteins, there are beta-integrin, cell adhesion molecule (CAM) and three types of collagens. All ESTs representing protease inhibitors and tumour-related proteins were found only in the WSSV-infected library. Those encoding for apoptotic peptides were expressed at high levels in infected library. The putative defence proteins accounted for 2.7% of total ESTs in a normal shrimp library and 15.7% of the total ESTs in an infected library.     

A novel gene (retinovin) expressed selectively in the early stage of chick retinal development

To understand molecular mechanisms of retinal development, genes expressed selectively only in the early stage of retinal development were isolated by subtractive hybridization based on suppression polymerase chain reaction. The retina has no layered structure in 7-day chick embryos, in contrast with the fully developed multilayered structure of neurons in 15-day embryos. The subtraction between cDNA derived from retinal tissues at these different stages, followed by repeat rounds of 5'-RACE (rapid amplification of cDNA ends) and 3'-RACE, led to isolation of a novel gene with an open reading frame encoding a putative protein with 753 amino acids. Its specific expression in the 7-day embryonic retina was confirmed by Northern blot analysis. The gene, named "retinovin," would be used as a marker for identifying retinal stem cells present at the early stage of retinal development.     

Host plant genotype influences survival of hybrids between Eurosta solidaginis host races

Extrinsic, host-associated environmental factors may influence postmating isolation between herbivorous insect populations and represent a fundamentally ecological cause of speciation. We investigated this issue in experiments on hybrids between the host races of Eurosta solidaginis, a fly that induces galls on the goldenrods Solidago altissima and S. gigantea. To do so, we measured the performance of parental host races and their hybrids on five genotypes of S. gigantea and nine genotypes of S. altissima to test hypotheses about how variation in plant genotype affects performance (i.e., fitness) and potentially influences gene flow between these host races. We found that rates of gall induction and of survival to adult emergence by hybrid larvae were significantly lower than those of both parental host races on both host species, adding support to the hypothesis that there is partial postmating isolation between the host races. Hybrid flies significantly varied in their performance across plant genotypes of both host species. A significant interaction between the effects of plant genotype and mating treatment (parental vs. hybrid crosses) on larval performance indicated that the relative suitability of particular plant genotypes differed between the parental host races and their hybrids. These patterns illustrate a poor correspondence between optimal parental and hybrid environments, consistent with the hypothesis that these host races are partially isolated due to extrinsic (ecological) factors. Based on these findings, we discuss the possibility that plant genotypes in which hybrid performance is high can facilitate hybridization and gene flow between partially reproductively isolated populations of herbivorous insects, thus affecting the dynamics of ecological speciation.     

Improved conception in timed-artificial insemination using a progesterone-releasing intravaginal device and Ovsynch protocol in postpartum suckled Japanese Black beef cows

The primary objective was to determine the effect of supplemental progesterone, administered via an intravaginal device (CIDR), on conception rates to timed-artificial insemination (timed-AI) in postpartum suckled Japanese Black beef cows treated with the Ovsynch protocol. A secondary objective was to compare the effects of treatments on plasma concentrations of progesterone and estradiol. Cows in the control group (Ovsynch, n=38) received a standard Ovsynch protocol (100 microg GnRH analogue on Day 0, 500 microg PGF2alpha analogue on Day 7, and 100 microg GnRH analogue on Day 9), with AI on Day 10, approximately 20 h after the second GnRH treatment. Cows in the treatment group (Ovsynch+CIDR; n=40) received a standard Ovsynch protocol plus a CIDR for 7 days (starting on Day 0). Plasma progesterone concentrations were determined on Days 0, 1, 7, 9, 10, and 17 and plasma estradiol-17beta concentrations were determined on Days 7, 9, 10, and 17. The odds ratio for likelihood of conception was 3.29 times greater (P=0.02) in the Ovsynch+CIDR group compared to Ovsynch group. The conception rate was greater (P=0.03) in the Ovsynch+CIDR group than in the Ovsynch group (72.5% versus 47.7%). Insertion of a CIDR device significantly increased plasma progesterone concentrations only on Days 1 and 7 (P<0.001 and P=0.05, respectively), but had no significant effect on plasma estradiol-17beta concentrations. Including a CIDR with the Ovsynch protocol significantly improved conception rates in postpartum suckled Japanese Black beef cows.     

Evolutionary and environmental effects on the geographical adaptation of herbivory resistance in native and introduced <Emphasis Type="Italic">Solidago altissima</Emphasis> populations

To understand rapid evolution in plant resistance to herbivory, it is critical to determine how the genetic correlation among resistances varies genetically and/or environmentally. We conducted a reciprocal transplant experiment of tall goldenrod, Solidago altissima with multiple replicates within the native range (USA) and the introduced range (Japan) to explore the differences in phenotypic traits of resistance to multiple herbivorous insects and their relationships between and within the countries. The Japanese plants were more resistant to the lace bug, Corythucha marmorata, which had recently invaded Japan, but were more susceptible to other herbivorous insects compared to the USA plants. An antagonistic relationship was found between plant resistances to lace bugs and other herbivorous insects in both USA and Japanese plants. In addition, this relationship was more obvious in gardens with a high level of foliage damage than in gardens with a low level of foliage damage by other herbivorous insects. An antagonistic relationship between resistances to aphids and lace bugs was also observed in USA gardens, but not in Japanese garden. These results suggest that the strength of constraints on the evolution of plant resistance due to genetic trade-offs may differ among biotic environments, including community structure of herbivorous insects. Therefore, differences in herbivorous insect communities between the native and introduced ranges can result in the rapid evolution of greater resistance in plants in the introduced range than in the native range.     

Deciphering the DNA repair protein, Rad23 from kuruma shrimp Marsupenaeus japonicus: full-length cDNA cloning and characterization

Aims: Lesions of DNA are removed by nucleotide excision repair (NER) process in the living systems. NER process‐related host factors are believed to aid recovery steps during viral integration. Here, we report identification and characterization of a DNA repair molecule Rad23 from kuruma shrimp Marsupenaeus japonicus. Methods and Results: The full‐length cDNA of M. japonicus Rad23 gene (MjRad23) has 1149 bp coding for a putative protein of 382 amino acids with a 5′ untranslated region (UTR) of 92 bp and 3′ UTR region of 1116 bp. Quantitative expression analysis revealed MjRad23 is constitutively expressed in all the organs of healthy shrimp, whereas with high level in muscle tissue. Although MjRad23 expression is observed in every haemolymph samplings to post‐white spot syndrome virus infection, high expression is recorded at 2 h post infection (h.p.i.). MjRad23 consists of putative functional domains including one ubiquitin domain (UBQ), two ubiquitin‐associated domains (UBA) and one heat‐shock chaperonin‐binding motif (STI1). Multiple alignment of MjRad23 with Rad23 of other species showed highly significant identity ranging from 37 to 53%; however, high homology is observed with Rad23 of Bombyx mori (BmRad23). UBQ domain region alignment revealed maximum of 66% homology with Rad23 of Apis melifera (AmRad23). MjRad23 clustered with invertebrate sector along with insect species in evolution analysis. Three‐dimensional structural analyses demonstrated the highest identity between MjRad23 and human Rad23A (hHR23A). Conclusions: The present work revealed the presence of MjRad23 gene, which is essential in DNA repair process. Further studies are required to clarify the involvement of MjRad23 in NER process. Significance and Impact of the Study: This is the first report on identification and characterization of DNA repair protein in crustaceans, which will lead to further investigation to explore the molecular mechanisms behind the NER process.     

Induction of transforming growth factor-beta 1 by androgen is mediated by reactive oxygen species in hair follicle dermal papilla cells

The progression of androgenetic alopecia is closely related to androgen-inducible transforming growth factor (TGF)-β1 secretion by hair follicle dermal papilla cells (DPCs) in bald scalp. Physiological levels of androgen exposure were reported to increase reactive oxygen species (ROS) generation. In this study, rat vibrissae dermal papilla cells (DP-6) transfected with androgen receptor showed increased ROS production following androgen treatment. We confirmed that TGF-β1 secretion is increased by androgen treatment in DP-6, whereas androgeninducible TGF-β1 was significantly suppressed by the ROSscavenger, N-acetyl cysteine. Therefore, we suggest that induction of TGF-β1 by androgen is mediated by ROS in hair follicle DPCs. [BMB Reports 2013; 46(9): 460-464]