The Physcomitrella genome reveals evolutionary insights into the conquest of land by plants

We report the draft genome sequence of the model moss Physcomitrella patens and compare its features with those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This comparison reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity; loss of genes associated with aquatic environments (e.g., flagellar arms); acquisition of genes for tolerating terrestrial stresses (e.g., variation in temperature and water availability); and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant's unique facility for reverse genetics.     

Inhibitory effects of oolong tea polyphenols on pancreatic lipase in vitro

Fifty-four polyphenols isolated from tea leaves were evaluated for their inhibitory activities against pancreatic lipase, the key enzyme of lipid absorption in the gut. (-)-Epigallocatechin 3-O-gallate (EGCG), which is one of major polyphenols in green tea, showed lipase inhibition with an IC50 of 0.349 microM. Moreover, flavan-3-ol digallate esters, such as (-)-epigallocatechin-3,5-digallate, showed higher activities of inhibition on lipase with an IC50 of 0.098 microM. On the other hand, nonesterified flavan-3-ols, such as (+)-catechin, (-)-epicatechin, (+)-gallocatechin, and (-)-epigallocatechin, showed zero and/or the lowest activities against pancreatic lipase (IC50 > 20 microM). These data suggested that the presence of galloyl moieties within the structure was required for enhancement of pancreatic lipase inhibition. It is well-known that flavan-3-ols are polymerized by polyphenol oxidase and/or heating in a manufacturing process of oolong tea. Oolonghomobisflavans A and B and oolongtheanin 3'-O-gallate, which are typical in oolong tea leaves, showed strong inhibitory activities with IC50 values of 0.048, 0.108, and 0.068 microM, respectively, even higher than that of EGCG. The oolong tea polymerized polyphenols (OTPP) were prepared for the assay from oolong tea extract, from which the preparation effectively subtracted the zero and/or less-active monomeric flavan-3-ols by preparative high-performance liquid chromatography. The weight-average molecular weight (Mw) and number-average molecular-weight (Mn) values of OTPP were 2017 and 903, respectively, by using gel permeation choromatography. OTPP showed a 5-fold stronger inhibition against pancreatic lipase (IC50 = 0.28 microg/mL) by comparison with that of the tannase-treated OTPP (IC50 = 1.38 microg/mL). These data suggested that the presence of galloyl moieties within their chemical structures and/or the polymerization of flavan-3-ols were required for enhancement of pancreatic lipase inhibition.     

Growth characteristics of canine distemper virus in a new cell line CCT cells originated from canine malignant histiocytosis

Canine distemper virus (CDV) growth and the morphological characterization were examined in a cell line established from a canine malignant histiocytosis (CCT cell line). The susceptibility of the CCT cells to 3 CDV strains, FXNO, YSA-TC and MD-77 was shown by detection of the antigen in the indirect fluorescent assay. After passaging 4 and 9 times through the CCT cells, only FXNO strain could produce the syncytia where demonstrated the antigens. Titers of 9 passaged viruses through the CCT cells showed slightly higher in the CCT cells than those in Vero cells. Morphological characterization of karyorrhexis and specific DNA ladder by extracted DNA electrophoresis indicated apoptosis in the CDV infected CCT cells.     

Insulin-like growth factor-I stimulated DNA replication in mouse endometrial stromal cells

Much evidence has suggested that sex steroid hormone-induced growth of uterine cells is mediated by polypeptide growth factors synthesized in uterine tissues. The present study aimed to clarify the effect of insulin-like growth factor-I (IGF-I) on the proliferation of mouse endometrial stromal cells obtained from immature mice. IGF-I and IGF-I receptor (type I) mRNAs were detected in the endometrial stromal cells. IGF-I increased bromodeoxyuridine (BrdU) uptake in the endometrial stromal cells, indicating an increase in DNA replication. E2 increased IGF-I mRNA levels in the endometrial stromal cells. IGF-I receptor is a tyrosine kinase receptor, and treatment with genistein, a tyrosine kinase inhibitor, reduced IGF-I-induced BrdU-uptake in the endometrial stromal cells. IGF-I signaling pathways involve mitogen-activated protein (MAP) kinase and phosphatidylinositol-3 kinase (PI-3 kinase). Treatment with 10(-7) M of the MAP kinase inhibitor PD098059 and 10(-5) M of the PI-3 kinase inhibitor LY294002 decreased IGF-I-induced BrdU-uptake in the endometrial stromal cells. However, LY294002 (10(-5) M) also decreased the BrdU-uptake in the absence of IGF-I treatment. These results suggest that endometrial IGF-I is involved in the proliferation of endometrial stromal cells in a paracrine or autocrine manner, and that the MAP kinase pathway is involved in DNA replication of endometrial stromal cells.     

Drilling to gabbro in intact ocean crust

Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D.     

Insulin-like Growth Factor 1 mRNA Expression in the Uterus of Streptozotocin-treated Diabetic Mice

Reproductive functions decline with the onset of diabetes in female mice. Diabetic mice have smaller uteri with an underdeveloped endometrium, suggesting diminished estrogen-induced growth. We aimed to clarify the changes in the estrous cycle and in insulin-like growth factor 1 (IGF1) expression in the uteri of streptozotocin (STZ)-treated diabetic mice, because IGF1 is one of the main growth factors involved in estrogen-induced uterine growth. ICR female mice were intraperitoneally administered STZ (10 mg/100 g BW), and blood glucose levels were determined. Mice with blood glucose levels > 200 mg/dl were classified as diabetic mice. The onset of diabetes was associated with acyclic estrous cycles. Diabetes was also induced with STZ in ovariectomized mice. Uterine Igf1 mRNA levels were reduced in ovariectomized STZ-treated diabetic mice. Estrogen is known to stimulate Igf1 mRNA expression in the uterus, but estrogen action was abolished in the uteri of STZ-treated diabetic mice. mRNA expressions of estrogen receptor α (ERα) and steroid hormone receptor coactivators (SRC-1/Ncoa1, SRC-2/Ncoa2, SRC-3/Ncoa3 and CBP/p300/Crebbp) were reduced in the uteri of ovariectomized STZ-treated diabetic mice. The present study demonstrates that diabetes induces a decline in female reproductive functions in mice. Igf1 expression in ovariectomized diabetic female mice was decreased, and decreased responsiveness to estrogen in the uteri of diabetic mice is probably associated with a reduction in ERα and steroid receptor coactivator mRNA expression.     

Establishment of reliable methods of in vitro pollen germination and pollen preservation of Brassica rapa (syn. B. campestris)

A simple and reliable method for evaluating the viability of Brassica pollen was established in which the in vitro germination rate of pollen was adopted as the index of the viability of pollen grains. Pollen grains were preincubated in an atmosphere in which the relative humidity (RH) was fixed to 52% or 66% at 20 °C for 5 hours. They were cultured for 16 hours at 25 °C in a liquid Kwack's medium (1964) supplemented with 20% sucrose, and the pH was adjusted to 8.0. They were then observed under a microscope and the number of germinating and unchanged pollen grains were counted. The germination rate of pollen was improved and stabilized by preincubation and the use of a high pH medium. More than 90% of the freshly harvested pollen grains of Brassica rapa (syn. B. campestris) germinated constantly in these conditions Undehisced anthers were collected from flowers at anthesis and dehydrated by incubation at 20 °C for 16–24 hours in an atmosphere where the RH was fixed to 15% or 32%. They were put into a plastic vial and preserved in a freezer at -20 °C. The germination percentage of the preserved pollen was scored at intervals during preservation. The germination rate of the pollen grains preserved at -20°C for 1 year was higher than 50% and the pollen proved to be efficient for seed set. Most of the seeds germinated normally. This revised version was published online in August 2006 with corrections to the Cover Date.     

Estrogen inhibits interleukin-18 mRNA expression in the mouse uterus

Interleukin-18 (IL-18) is a proinflammatory cytokine expressed in female reproductive organs in humans, rats and mice. The physiological roles of uterine IL-18 and the regulatory mechanisms of IL-18 gene expression are unclear. The present study aimed to clarify the effects of estradiol-17beta (E2) and progesterone (P4) on IL-18 mRNA expression in the mouse uterus. Distribution and expression levels of IL-18 mRNA were studied using an RNase protection assay. Expression of IL-18 mRNA was observed in all organs studied, including testes, ovaries and uteri. The uterine IL-18 mRNA level of estrous mice was higher than that of diestrous mice. E2 treatment (1, 5, 25 or 250 ng/mouse) decreased uterine IL-18 mRNA levels in ovariectomized mice dose-dependently. E2 treatment acutely decreased IL-18 mRNA levels 3 h after injection, but these levels returned to the initial level after 48 h. P4 treatment (1 mg/mouse) decreased uterine IL-18 mRNA levels after 12 h, but levels returned to the initial level after 48 h. Both uterine IL-18 and IL-18Ralpha mRNAs were detected in cultured endometrial epithelial and stromal cells. These results suggest that uterine IL-18 expression is reduced by sex steroid hormones and that IL-18 acts on endometrial cells in a paracrine or autocrine manner.