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The taxonomy of Paphiopedilum Pfitz. has been disputed and needs more data for clarification. Floral morphology and anther development in P. purpuratum were observed using microscope and paraffin section. The results were as follows:(1)It was supported that P. purpuratum should be placed in Paphiopedilum subgenus Paphiopedilum sect. Barbata by some floral features, including a single flower, sepal white with veins, petal spotted with blackish-maroon, pouch of a lip auriculate on both sides, and a staminode lunate.(2)At the early stage, anther primordium developed into a pair of laterally juxtaposed thecae. An incomplete sterile septa was differentiated in the center of each theca, giving rise to two arc-shaped microsporangia. When anther split, the sterile septum was discomposed and degenerated resulting in a mass of sticky pollens from two pollen sacs were fused into a unit.(3)The developed anther wall consisted of an epidermis, an endothecium, a middle layer, and a tapetum, conforming to the monocotyledonous type. Both tapetum and the inner tapetum cells contained 2 nuclei. At the stage of 2-celled grains, degeneration occurred in the epidermis and tapetum layers, while the endothecium became thickened fibrously.(4)Microspore mother cells underwent a simultaneous cytokinesis resulting in microspore tetrads with varied arrangements of tetrahedral, isobilateral, and decussate types, and the meiotic activity of microspore mother cells in the same theca was obviously asynchronous and different meiosis phases could be observed.(5)Microspores produced 2-celled pollens via a mitosis, which could be retained in pollen tetrads or released as monad. Based on the data available, some key features are selected for taxonomy and conservation biology of Paphiopedilum in Cypripedioideae, including the differentiation of incomplete sterile septum, the monocotyledonous type of anther wall, the binucleated tapetum, differentiation of the inner tapetum, simultaneous cytokinesis, the sticky pollens, and so on. This study provides new information for taxonomy and conservation biology of Paphiopedilum, as well as of Cypripedioideae. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Asclepiadaceae s. str. and Apocynaceae s. str. have been combined as a monotypic family of Apocynaceae s. l. based on molecular data, including 5 subfamilies and 25 tribes. However, the relationships between subfamilies and tribes are complicated and needed to be further clarified. Sporogenesis and gametogenesis in Chinese endemic plant of Dregea sinensis var. sinensis(trib. Marsdenieae, subfam. Asclepiadoideae)were investigated using paraffin sectioning, and then the observed embryological characters were compared with those of five subfamilies for taxonomic insights. The results were as follows:(1)The anther was comprised of two lateral thecae containing a pair of pollinia.(2)The developed anther wall consisted of six layers, including an epidermis, two layers of endothecium, a middle layer, and 2-layered tapetum. So, the anther wall development was of Massive type.(3)The tapetum was uni-nucleated,2-layered, and of glandular type. Endothecium developed fibrous thickenings heavily and a slit occurred at abaxial position of each theca when anther was ripened.(4)The microspore mother cells underwent meiosis with a successive cytokinesis and produced microspore tetrads with isobilateral arrangement. The microspores retained in tetrads developed into 3-celled pollens by mitosis twice, which formed a compact pollinium.(5)The pistil was composed of two separate carpels containing many anatropous, tenuinucellar, and unitegmic ovules with marginal parietal placentations. The development of embryo sac conformed to the Polygonum type. These embryological features observed added new data to the tribe Marsdenieae. It was confirmed that the recognition of a monophyletic Apocynaceae s. l. was supported by some distinguished and related embryological characters among five subfamilies. [ABSTRACT FROM AUTHOR]

Ten-eleven translocation 3 (TET3), one member of TET family, is a dioxygenase that depends on Fe2+ and α-ketoglutarate (α-KG). TET3 can oxidize 5-methylcytosine (5-mC) to 5-hydroxymethylcytosine (5- hmC) and complete the regulation of gene expression. Studies showed that the expression of TET3 was not only up -regulated during neural differentiation, but also sustained during gametogenesis, and that TET3 played an important role in regulating the early embryonic development and activation. In other words, the TET3-mediated gene expression and regulation are involved in the mammalian reproduction and embryonic development. The structure of TET3 protein, the roles of TET3 in regulating gametogenesis and embryonic development, and other TET3-related biological functions, were reviewed in this paper, so as to promote the functional research of TET3 and the application in the field of life sciences. [ABSTRACT FROM AUTHOR]

Phthalates (PAEs) are widely used as additives in food, building materials, medical and other industries. Because PAEs are difficult to form strong covalent bonds, they will continue to leak into the environment and be absorbed during people's daily life. As a large class of environmental endocrine disruptors that disrupt reproductive endocrine, PAEs affect gametes and embryo development strongly. The factors of Wnt family participate in the regulation of tissue differentiation, growth and development via multiple mechanisms such as affecting gene expression and inducing cell proliferation. This paper reviews the biochemical character, endocrine disruption mechanisms and pollution conditions of PAEs, and the related Wnt signaling pathways that may affect gametes and embryo development. [ABSTRACT FROM AUTHOR]

The polyamines are a group of ubiquitous polycationic compounds, including spermine, spermidine and putrescine. Mammals synthesize polyamines de novo from amino acids or intake these compounds from food. These compounds participate in the regulation of oxidative stress by eliminating the excess reactive oxygen species (ROS). The polyamines are essential to reproduction and embryo/fetal development. Studies indicate that the polyamines are regulators of cell growth and gene expression, and both mitosis and meiosis. In male reproduction, the polyamines are correlated with spermatogenesis and sperm motility. In female mammals, the polyamines are involved in follicle development and ovulation, and steroidogenesis in the ovary. The additional polyamines can effectively reduce the rate of oocyte aneuploidy and improve the embryonic development in in vitro maturation (IVM). Furthermore，the absence of polyamines can lead to the arrest of embryogenesis. The polyamines are also involved in placental development and material exchange between mother and fetal. This article reviews the biological functions of polyamines and their effects on gametogenesis and placental development. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

N6-methyl-adenosine （m6A）,one of the most common modifications of more than 100 methylation on RNA molecules, plays an important biological role. With the application of the m6A RNA immunoprecipitation approach followed by high-throughput sequencing （MeRIP-SEQ） and the discovery of three kinds of proteins, methyltransferase,demethylase and m6A-binding proteins, the m6A was identified to be a kind of dynamic and reversible modification of RNA methylation. The m6A plays its roles just via the＂writing＂, ＂erasering＂and ＂reading＂ methyl of RNA by the above three kinds of proteins. To our knowledge,m6A regulates many biological procedures, such as gametogenesis,gonadal development, embryo development, as well as RNA metabolism. This reversible RNA methylation is a post-transcriptional regulation of gene expression, especially in the gametogenesis, which is a new research field in reproductive medicine. [ABSTRACT FROM AUTHOR]

Genomic imprinting is a mechanism of differentially epigenetic modification that restricts monoallelic expression to either the maternally or paternally inherited copy of the gene during gametogenesis. Imprinted methylation undergoes a process of erasure, acquisition, and maintenance during gametogenesis and early embryogenesis. Disruptions in any of these steps may lead to imprinting disorders, resulting in the aberrant development of embryogenesis, placentation and postnatal growth. Recent studies have shown that maternal-effect proteins are important for the regulation of imprinted gene during the development of preimplantation embryos. In order to obtain a better understanding for the mechanism of maternal-effect proteins in the maintenance of genomic imprints, the recent study progress of maternal-effect proteins, such as DPPA3, ZFP57, TRIM28 and DNMT1, are summarized, and the regulation mechanism of these maternal-effect proteins for genomic imprints are discussed.

Polysaccharide and lipid in the anthers of Lycium barbarurn L. at different stages were examined with cytochemical techniques. At the stage of sporogenous cell, many starches have been storied in parenchyma around vascular bundle, epidermis and endothecium cells but no starches in sporogenous cells, tapetal and middle layer cells. At the stage of tetrad, there were many starches still in epidermis and endothecium, however tapetal cells began to accumulate lipid drops, suggesting that tapetal cells transformed polysaccharides into lipid. Tapetum degenerated at the late stage of microspore and the lipid drops moved into locule. During microspore development neither starches nor lipid drops were accumulated in the cell. After the division of microspore, some lipids drops appeared in 2-cellular pollen, and then some starches also appeared in the pollen. Two days before anthesis, there were many lipid drops and starches located in nearly mature pollen grains, suggesting that pollen of Lycium barbarurn L. has a function of transforming lipid into polysaccharide. The temporal and spatial features of polysaccharide and lipid material accumulated and distributed in anther during its development reflect the transformation of physiological function of the cells consisting of anther. This research will help us to understand the mechanism of anther development.