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21.
Yo Morimoto Jun-ya Shibata Mizuki Takahata Omar Myint Masanori Kohda 《Journal of Ethology》2010,28(3):429-436
Like many other gobies, male Isaza (Gymnogobius isaza) which are endemic to Lake Biwa, Japan, exclusively care for broods in nests. This goby may have an optimal range of brood
size (i.e., an average clutch size of about 2000–3000 eggs) within which they may produce larger numbers of hatching young
because much larger broods may be destroyed by fungal infection before hatching. This optimal brood size hypothesis (Takahashi
et al. in J Ethol 22:153–159, 2004) predicts that (1) after spawning, both males and females will refuse additional spawning by other gravid females (second
females) to keep brood sizes within optimal ranges, (2) larger fish will repel second females more successfully than will
smaller fish, and thus, (3) both sexes prefer larger mates. To examine these predictions, we first observed Isaza’s aggressive
behaviors in aquaria and investigated whether fish attacked and repelled second females that were introduced after spawning,
and, if so, what were the sizes of fish that did so. Large fish, regardless of sex, aggressively prevented second females
from entering the nest, but second females larger than the pairs displaced the pair females forcibly and spawned eggs into
their clutches. Mate choice experiments showed that males preferred large females. Although females’ choice of large mates
was not confirmed, many results may largely coincide with the predictions of the optimal brood size hypothesis. Thus, Isaza
males’ choice of large mates will be advantageous for defending against brood parasitism by conspecific females and for achieving
optimal clutch size. 相似文献
22.
Inamori Y Ota M Inoko H Okada E Nishizaki R Shiota T Mok J Oka A Ohno S Mizuki N 《Human genetics》2007,122(2):151-157
The collagen type Ι alpha Ι (COL1A1) gene encodes the extracellular matrix component, collagen, and resides in candidate MYP5
for high myopia on the chromosome 17q22–q23.3. This locus has recently been implicated in playing an important role in the
pathogenesis of experimental myopia. We investigated the association of disruptions of COL1A1 gene with high myopia by analyzing the frequency of ten SNPs in a Japanese population of 330 subjects with high myopia of
−9.25 D or less and 330 randomized controls without high myopia. Two SNPs (rs2075555 and rs2269336) were significantly associated
with high myopia (P < 0.05, Pc < 0.1). Two different haplotype blocks in COL1A1 were observed by the pair-wise linkage disequilibrium between the SNPs. The frequency of GGC/GGC diplotype constructed by
the three SNPs (rs2075555, rs2269336, rs1107946) was significantly high (OR = 1.6) and associated with high myopia (P = 0.028, Pc< 0.084). Together our results provide the first evidence for COL1A1 as a gene associated with high myopia. 相似文献
23.
Jonathan S. Griffiths Kre?imir ?ola Rekha Kushwaha Patricia Lam Mizuki Tateno Robin Young C?t?lin Voiniciuc Gillian Dean Shawn D. Mansfield Seth DeBolt George W. Haughn 《Plant physiology》2015,168(2):502-520
CELLULOSE SYNTHASE5 (CESA5) synthesizes cellulose necessary for seed mucilage adherence to seed coat epidermal cells of Arabidopsis (Arabidopsis thaliana). The involvement of additional CESA proteins in this process and details concerning the manner in which cellulose is deposited in the mucilage pocket are unknown. Here, we show that both CESA3 and CESA10 are highly expressed in this cell type at the time of mucilage synthesis and localize to the plasma membrane adjacent to the mucilage pocket. The isoxaben resistant1-1 and isoxaben resistant1-2 mutants affecting CESA3 show defects consistent with altered mucilage cellulose biosynthesis. CESA3 can interact with CESA5 in vitro, and green fluorescent protein-tagged CESA5, CESA3, and CESA10 proteins move in a linear, unidirectional fashion around the cytoplasmic column of the cell, parallel with the surface of the seed, in a pattern similar to that of cortical microtubules. Consistent with this movement, cytological evidence suggests that the mucilage is coiled around the columella and unwinds during mucilage extrusion to form a linear ray. Mutations in CESA5 and CESA3 affect the speed of mucilage extrusion and mucilage adherence. These findings imply that cellulose fibrils are synthesized in an ordered helical array around the columella, providing a distinct structure to the mucilage that is important for both mucilage extrusion and adherence.The epidermal cells of Arabidopsis (Arabidopsis thaliana) seed coats produce two distinct secondary cell walls: pectin-rich mucilage and cellulose-rich columellae (Western et al., 2000). When seeds are hydrated, mucilage expands rapidly, rupturing the outer tangential cell wall and forming a mucilage capsule that surrounds the seed. Seed coat mucilage is composed primarily of rhamnogalacturonan I (RG I) and also contains homogalacturonan (HG), hemicelluloses (such as xylans and glucomannans), and cellulose (for review, see Haughn and Western, 2012). Extruded mucilage consists of an outer, nonadherent fraction and an inner, adherent fraction (Western et al., 2000, 2001; Macquet et al., 2007a). The adherent and nonadherent mucilage layers differ in the amount of methylesterified HG (Rautengarten et al., 2008; Saez-Aguayo et al., 2013; Voiniciuc et al., 2013), galactans (Dean et al., 2007; Macquet et al., 2007b), arabinans (Arsovski et al., 2009), mannans (Yu et al., 2014), and cellulose (Harpaz-Saad et al., 2011; Mendu et al., 2011; Sullivan et al., 2011), all of which influence the physical properties of the layers.Adherent mucilage has a distinct structure, which can be examined using cell wall dyes and antibodies. When treated with cellulose-specific dyes, densely stained rays extend from the top of each columella to the outer edge of the adherent layer, many cell lengths above the seed surface (Mendu et al., 2011; Sullivan et al., 2011). Cytological evidence indicates that cellulose, pectins, and mannans are components of the ray (Haughn and Western, 2012; Griffiths et al., 2014; North et al., 2014; Yu et al., 2014), although the exact manner in which they are assembled is unknown.Cellulose is abundant in mucilage rays and mediates adherence. Loss-of-function mutations in CELLULOSE SYNTHASE5 (CESA5) result in reduced cellulose levels and increased detachment of mucilage from the seed (Harpaz-Saad et al., 2011; Mendu et al., 2011; Sullivan et al., 2011; Griffiths et al., 2014). How a reduction in cellulose results in a loss of adherence is still unknown, but it likely involves interaction with other mucilage components such as pectin and arabinogalactan proteins (Griffiths et al., 2014). Since cesa5 mutants still have some cellulose in the rays of the adherent mucilage halo (Mendu et al., 2011; Sullivan et al., 2011), additional cellulose synthases must be involved in mucilage cellulose biosynthesis.The Arabidopsis genome encodes 10 different CESAs (Delmer, 1999; Richmond and Somerville, 2000). Multiple lines of evidence suggest that three different CESAs are required to form one active cellulose synthase complex (CSC; for review, see Somerville, 2006). CSCs are membrane-bound protein complexes that synthesize cellulose microfibrils in the apoplast (for review, see Somerville, 2006; Endler and Persson, 2011; Lei et al., 2012). CESA1, CESA3, and CESA6 are considered the core components of the primary wall CSC (Desprez et al., 2007; Persson et al., 2007). CESA2, CESA5, and CESA9 are partially redundant to CESA6 in primary wall biosynthesis, and genetic evidence suggests that each of these CESA polypeptides can form a functional CSC with CESA3 and CESA1 (Desprez et al., 2007; Persson et al., 2007). CESA10 is expressed in young plants, stems, floral tissue, and the base of rosette leaves (Beeckman et al., 2002; Doblin et al., 2002), but its function in cellulose biosynthesis is unclear. Other cesa mutant lines have been examined for altered mucilage phenotypes (cesa1, radially swollen1 [Burn et al., 2002; Sullivan et al., 2011], cesa2, cesa6, and cesa9 [Mendu et al., 2011]; CESA3, je5 [Sullivan et al., 2011] and cesa10-1 [Sullivan et al., 2011]); to date, only CESA5 has been shown to be required for cellulose biosynthesis during mucilage deposition.Two mutant alleles of CESA3, isoxaben resistant1-1 (ixr1-1) and ixr1-2, were isolated in a screen for resistance to the herbicide isoxaben (Scheible et al., 2001). Isoxaben inhibits the incorporation of Glc into the emerging cellulose polymer and is considered a potent and specific inhibitor of cellulose biosynthesis (Heim et al., 1990). Homozygous ixr1-1 and ixr1-2 lines show increased resistance to the herbicide, and the mutations causing this resistance were mapped to the genomic locus of CESA3 (Heim et al., 1990; Scheible et al., 2001). The ixr1-1 and ixr1-2 mutations cause amino acid substitutions near the C terminus of the CESA3 protein. ixr1-1 causes a Gly-to-Asn substitution (G998A) located in a transmembrane domain, while ixr1-2 contains a Thr-to-Ile substitution (T942I) in an apoplastic region of the protein between two transmembrane domains (Scheible et al., 2001). Recently, the ixr1-2 allele was shown to affect the velocity of CSCs in the plasma membrane, which consequently modifies cellulose crystallinity in the cell wall (Harris et al., 2012). It is not exactly clear how the ixr1-1 mutation affects cellulose biosynthesis. The effects of either of these mutations on seed coat mucilage have not been investigated.Since mucilage is composed primarily of pectins with smaller amounts of cellulose, seed coat epidermal cells represent an excellent system to study cellulose biosynthesis and interactions between cellulose and other wall components in muro. In this study, we investigated how cellulose is synthesized and deposited in seed coat epidermal cells. We show that at least three different CESA proteins are highly expressed in the seed coat epidermis during mucilage biosynthesis. These CESAs are oriented and move in a linear fashion around the cytoplasmic column of each cell in an identical pattern to cortical microtubules. In addition, we provide evidence that the adherent mucilage has a helical structure that expands and unwinds during extrusion to form the mucilage ray. We propose that during seed coat epidermal cell development, the biosynthesis of cellulose predetermines the structure of rays in the adherent mucilage layer. 相似文献
24.
25.
Seto Y Kogami Y Shimanuki T Takahashi K Matsuura H Yoshihara T 《Bioscience, biotechnology, and biochemistry》2005,69(8):1515-1519
Epichloe typhina is an endophytic fungus, while Cladosporium phlei is a pathogenic fungus of the timothy plant (Phleum pretense L.). We found two activities in the culture filtrate of E. typhina: one stimulated the pathogenic fungus, C. phlei, to produce phleichrome and the other inhibited its growth. The active ingredients that stimulated the production of phleichrome and inhibited the growth of C. phlei were isolated and characterized. The isolated compounds were identified as cyclo-(L-Pro-L-Leu) and cyclo-(L-Pro-L-Phe), which were stimulatory compounds, and p-hydroxybenzaldehyde, which was the growth inhibitory compound, based on an analysis of their spectral data. Of the two stimulatory compounds, cyclo-(L-Pro-L-Phe) showed higher activity. However, when 500 microg of cyclo-(L-Pro-L-Phe) was spotted on the TLC plate for bio-autography, a growth inhibitory zone was identified in the central red region, which contained phleichrome. On the other hand, phleichrome showed antifungal activity against E. typhina in the light, so it is assumed that there might be antagonism between the endophytic fungus, E. typhina, and the pathogenic fungus, C. phlei. 相似文献
26.
Fukushima T Mizuki T Echigo A Inoue A Usami R 《Extremophiles : life under extreme conditions》2005,9(1):85-89
A halophilic archaeon, Haloarcula sp. strain S-1, produced extracellular organic solvent-tolerant -amylase. Molecular mass of the enzyme was estimated to be 70 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This amylase exhibited maximal activity at 50°C in buffer containing 4.3 M NaCl, pH 7.0. Moreover, the enzyme was active and stable in various organic solvents (benzene, toluene, and chloroform, etc.). Activity was not detected at low ionic strengths, but it was detected in the presence of chloroform at low salt concentrations. On the other hand, no activity was detected in the presence of ethyl alcohol and acetone. 相似文献
27.
Yamashita S Katayama H Saitoh H Akao T Park YS Mizuki E Ohba M Ito A 《Journal of biochemistry》2005,138(6):663-672
Bacillus thuringiensis strain A1462 produced two parasporal inclusion proteins with a molecular mass of 88 kDa that were converted to 64-kDa toxins when activated by proteinase K digestion. Both toxins exhibited strong cytocidal activity against two human cancer cell lines, HL60 (myeloid leukemia cells) and HepG2 (liver cancer cells), while low or no toxicities were observed against 11 human and three mammalian cell lines, including four non-cancer cell lines. The cytotoxicity of both toxins on susceptible cells was characterized by rapid cell swelling. Gene cloning experiments provided two novel genes encoding 88-kDa Cry proteins, Cry41Aa and Cry41Ab. The amino acid sequences of the two proteins contain five block regions commonly conserved in B. thuringiensis insecticidal Cry proteins. This is the first report of the occurrence of typical three-domain Cry proteins with cytocidal activity preferential for cancer cells. 相似文献
28.
Inage-Miyake Y Shimanuki S Itoh T Murakami Y Kimura M Suzuki H Miyake M Toki D Uenishi H Awata T Hamasima N 《Biochemical genetics》2005,43(1-2):79-85
We have obtained a partial cDNA and three BAC clones for the porcine insulin-like growth factor binding protein 1 gene (IGFBP-1). Results of fluorescence in situ and radiation hybrid (RH) mapping assigned this gene to porcine chromosome (SSC) 18q24-qter. We found two types of polymerase chain reaction–restriction-fragment-length polymorphisms (PCR–RFLP) in intron 2 by using FokI and AluI. 相似文献
29.
Shimanuki S Mikawa A Miyake Y Hamasima N Mikawa S Awata T 《Biochemical genetics》2005,43(9-10):491-500
Many quantitative trait loci (QTL) for growth and reproductive traits have been detected on the porcine chromosome region 1qter (SSC1qter), making it one of the most important genomic regions for pig breeding. SSC1q corresponds to human chromosome 9, on which lies transforming growth factor beta receptor 1 (TGFBR1). We cloned the porcine TGFBR1 cDNA and gene (as a candidate for QTL) and analyzed the gene structure and polymorphism. Porcine TGFBR1 consists of 9 exons and 8 introns. Intron 2 is alternatively spliced at the acceptor site, resulting in two kinds of mRNA, with putative open reading frames of 1500 and 1512 bp in length. The shorter one encodes 499 amino acid residues. The amino acid sequence has 96.2 and 97.2% sequence similarity to those of human and bovine TGFBR1, respectively. The sequence similarity between porcine and murine TGFBR1 is 95.6%. We detected three single-nucleotide substitutions in exons 1, 2, and 7. Those in exons 1 and 7 are nonsynonymous substitutions resulting in Pro8Ser and Ile413Val substitutions, respectively. 相似文献
30.
Takaaki Kobayashi Mizuki Watanabe Akira Yoshida Shizuo Yamada Mika Ito Hiroshi Abe Yoshihiro Ito Mituhiro Arisawa Satoshi Shuto 《Bioorganic & medicinal chemistry》2010,18(3):1076-1082
On the basis of the previous results on a histamine H4 receptor agonist 4-methylhistamine and a cyclopropane-based conformationally restricted analog CEIC (3) with potent H3/H4 receptor antagonistic effect, 4-methylhistamine analogs 4 and 5 of CEIC were designed and synthesized. Compound 4 showed strong affinity (Ki = 38.7 nM) for the H3 receptor, which was more potent than a well-known H3 antagonist thioperamide. Stable tautomer and conformation of 3 and 4, which can affect the pharmacological activity, were analyzed by ab initio calculations. 相似文献