Adhesion of pollen grains to the stigmatic surface is a critical step during sexual reproduction in plants. In Brassica, S locus-related glycoprotein 1 (SLR1), a stigma-specific protein belonging to the S gene family of proteins, has been shown to be involved in this step. However, the identity of the interacting counterpart in pollen and the molecular mechanism of this interaction have not been determined. Using an optical biosensor immobilized with S gene family proteins, we detected strong SLR1-binding activity in pollen coat extracts of Brassica campestris. Two SLR1-binding proteins, named SLR1-BP1 and SLR1-BP2, were identified and purified by the combination of SLR1 affinity column chromatography and reversephase HPLC. Sequence analyses revealed that these two proteins (i) differ only in that a proline residue near the N terminus is hydroxylated in SLR1-BP1 but not in SLR1-BP2, and (ii) are members of the class A pollen coat protein (PCP) family, which includes PCP-A1, an SLG (S locus glycoprotein)-binding protein isolated from Brassica oleracea. Kinetic analysis showed that SLR1-BP1 and SLR1-BP2 specifically bound SLR1 with high affinity (Kd ؍ 5.6 and 4.4 nM, respectively). The SLR1-BP gene was specifically expressed in pollen at late stages of development, and its sequence is highly conserved in Brassica species with the A genome. Sexual reproduction in plants depends on highly specific interactions between pollen and the pistil. These interactions are the basis of interspecific and intraspecific recognition systems, which allow the pistil to distinguish among genetically diverse ranges of pollen grains arriving at the stigma. Germination and growth of ''appropriate'' pollen grains are selectively promoted, whereas ''inappropriate'' pollen grains are selectively inhibited. One notable example of an intraspecific recognition system is self-incompatibility (SI) (1).In Brassica, SI is controlled by a single polymorphic locus, termed the S locus. Two stigmatically expressed polymorphic genes have been identified at the S locus. One is the S locus glycoprotein (SLG) gene, which encodes a secreted glycoprotein (2, 3), and the other is the S locus receptor kinase (SRK) gene, which encodes a receptor-like serine͞threonine protein kinase (4). SRK is the sole determinant of the S haplotype specificity of the stigma (5); its extracellular domain, which is highly similar to SLG, is thought to interact with the pollen S determinant of the same S haplotype. Recently, the gene encoding the pollen S determinant has been identified (6-8). This gene, designated SP11 (S locus protein 11) or SCR (S locus cysteine-rich), encodes a novel class within a family of proteins named the pollen coat protein (PCP) family (9, 10). It is hypothesized that interactions between SP11͞SCR and SRK elicit a signaling cascade within the surface cells of the stigma, the papillae, leading to the rejection of self-pollen. The role of SLG in SI is enhancing the recognition process between the stigma and self-pollen (5).The Brassica genome contai...
Quantitative microdilution plate hybridization was used to identify 22 Mycobacterium species. DNAs of clinical strains were rapidly extracted and labeled with photoreactive biotin. Labeled DNAs were distributed into wells of a microdilution plate in which reference DNAs had been immobilized. After 2 h of hybridization, hybridized DNAs were quantitatively detected with peroxidase-conjugated streptavidin and the substrate, tetramethylbenzidine. This method could differentiate among 20 of the 22 Mycobacterium species tested. The type strains of Mycobacterium tuberculosis and M. bovis were genetically highly related and could not be differentiated by this method. Of 194 biochemically identified human clinical strains, 178 (90%) were genetically identified within 3 h of the small-scale DNA extraction.
Aim : Although perineal approaches for radical prostatectomy have recently gained renewed attention as excellent methods for minimally invasive surgery, the most commonly used techniques, Belt's and Young's approaches, have inadequacies regarding the topographical relationship between the rectourethral and levator ani muscles. Methods : Using macroscopic observations of sagittal slices of 27 male pelvises and smooth muscle immunohistochemical staining of semiserial sections of another eight pelvises, we investigated the topographical anatomy of the perineal structures and their interindividual variations in elderly Japanese men.Results : The inferomedial edge of the levator ani was located 5-15 mm lateral to the midsagittal plane in an area between the urethra and the rectum. The rectourethral smooth muscle had a superoinferior thickness of 5-10 mm and occupied a space between the right and left levator slings. The levator was adjacent to, or continuous with, the striated anal sphincters. A thick connective tissue septum, composed of smooth muscle, was evident between the rectal smooth muscle and the anal sphincter-levator ani complex. Conclusion : Because the connective tissue septum guides the surgeon's finger upwards towards the rectoprostatic space, Belt's approach appears relatively easy; however, rectal injury can sometimes occur if the surgeon loses this guidance. In contrast, if the levator edge is identified as the first step in Young's approach, the rectourethral muscle can be precisely divided, leaving a 3-5-mm margin from the rectum and sphincter-levator complex. Clinical investigations are now required to modify Young's approach based on the present results.
Although ER beta is known to be expressed at high levels in the rat prostate gland, its regulation is not well understood. Here we examined ER mRNA expression and the effects of testosterone administration in male rats at 1, 4 and 9 weeks of age who were castrated and/or treated with testosterone for a week, and then sacrificed. ER alpha was the major type of ER expressed in 2 week-old animals while dominant expression of ER beta mRNA was apparent in older age groups. Interestingly while ER beta expression was diminished and ER alpha mRNA increased in the castrated group, testosterone administration reversed this effect. A time-course study indicated that induction of ER beta mRNA increased within 9 hr and ER alpha decreased in 2 days after an injection (i.p.) of testosterone. Our results suggested that 1) testosterone up-regulates ER beta mRNA expression while ER alpha is down-regulated; and that 2) great changes in ER alpha and beta expression in the prostate gland during development from the newborn to adult may be due to the influence of testosterone.
Adhesion of pollen grains to the stigmatic surface is a critical step during sexual reproduction in plants. In Brassica, S locus-related glycoprotein 1 (SLR1), a stigma-specific protein belonging to the S gene family of proteins, has been shown to be involved in this step. However, the identity of the interacting counterpart in pollen and the molecular mechanism of this interaction have not been determined. Using an optical biosensor immobilized with S gene family proteins, we detected strong SLR1-binding activity in pollen coat extracts of Brassica campestris. Two SLR1-binding proteins, named SLR1-BP1 and SLR1-BP2, were identified and purified by the combination of SLR1 affinity column chromatography and reversephase HPLC. Sequence analyses revealed that these two proteins (i) differ only in that a proline residue near the N terminus is hydroxylated in SLR1-BP1 but not in SLR1-BP2, and (ii) are members of the class A pollen coat protein (PCP) family, which includes PCP-A1, an SLG (S locus glycoprotein)-binding protein isolated from Brassica oleracea. Kinetic analysis showed that SLR1-BP1 and SLR1-BP2 specifically bound SLR1 with high affinity (Kd ؍ 5.6 and 4.4 nM, respectively). The SLR1-BP gene was specifically expressed in pollen at late stages of development, and its sequence is highly conserved in Brassica species with the A genome. Sexual reproduction in plants depends on highly specific interactions between pollen and the pistil. These interactions are the basis of interspecific and intraspecific recognition systems, which allow the pistil to distinguish among genetically diverse ranges of pollen grains arriving at the stigma. Germination and growth of ''appropriate'' pollen grains are selectively promoted, whereas ''inappropriate'' pollen grains are selectively inhibited. One notable example of an intraspecific recognition system is self-incompatibility (SI) (1).In Brassica, SI is controlled by a single polymorphic locus, termed the S locus. Two stigmatically expressed polymorphic genes have been identified at the S locus. One is the S locus glycoprotein (SLG) gene, which encodes a secreted glycoprotein (2, 3), and the other is the S locus receptor kinase (SRK) gene, which encodes a receptor-like serine͞threonine protein kinase (4). SRK is the sole determinant of the S haplotype specificity of the stigma (5); its extracellular domain, which is highly similar to SLG, is thought to interact with the pollen S determinant of the same S haplotype. Recently, the gene encoding the pollen S determinant has been identified (6-8). This gene, designated SP11 (S locus protein 11) or SCR (S locus cysteine-rich), encodes a novel class within a family of proteins named the pollen coat protein (PCP) family (9, 10). It is hypothesized that interactions between SP11͞SCR and SRK elicit a signaling cascade within the surface cells of the stigma, the papillae, leading to the rejection of self-pollen. The role of SLG in SI is enhancing the recognition process between the stigma and self-pollen (5).The Brassica genome contai...
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