• Title/Summary/Keyword: Tapetum

Search Result 18, Processing Time 0.025 seconds

Molecular Characterization of Brassica Pollen Allergen

  • Toriyama, Kinya;Okada, Takashi
    • Journal of Plant Biotechnology
    • /
    • v.2 no.2
    • /
    • pp.97-99
    • /
    • 2000
  • Allergy to Brassica pollen has been reported in some countries. We have cloned a cDNA encoding a Brassica pollen allergen, Bra r 1. Bra r 1 belongs to a new family of $Ca^{2+}$-binding proteins, characterized by the presence of two EF-hand calcium-binding domains. Bra r 1 was detected in the tapetum, microspores, pollen coat and pollen tubes, indicating Bra r 1 is involved in pollen pistil interaction and pollen tube growth. We have engineered the hypoallergenic mutants of Bra r 1 for immunotherapy. Here we describe the review of molecular characterization of Bra r 1.

  • PDF

Study on the Fine Structure of Retina of Anterior Lateral Eyes in Pardosa astrigera L. Koch (Aranea: Lycosidae) (별늑대거미 (Pardosa astrigera L. Koch) 전측안(前側眼) 망막(綱膜)의 미세구조(微細構造)에 관한 연구)

  • Jeong, Moon-Jin;Moon, Myung-Jin
    • Applied Microscopy
    • /
    • v.24 no.3
    • /
    • pp.1-9
    • /
    • 1994
  • Pardosa astrigera possessed eight eyes arranged in three rows on the frontal carapace. A pair of small anterior lateral eyes (ALE) flanked each side by an anterior median eyes (AME) lay along the anterior margin that was situated on the anterior row of clypeus. The anterior lateral eye was composed of cornea, vitreous body, and retina. Cornea was made up mainly of exocuticle lining the cuticle. Lens in anterior lateral eye was biconvex type which bulged into the cavity of the eyecup. Outer and inner central region of lens were approximately spherical with radius of curvature $5.6{\mu}m$ and $12.5{\mu}m$, respectly. Vitreous body formed a layer between the cuticular lens and retina. They formed biconcave shape. Retina of the anterior lateral eyes was composed of three types of cells: visual cells, glia cells, and pigment cells. The visual cells were unipolar neuron, as were the receptor of the posterior lateral eye. But cell body was unique to the anterior lateral eyes. They were giant cell, relatively a few in number, and under the layer of vitreous bodies. Each visual cell healed rhabdomeres for a short stretch beneath the cell body. Rhabdomes were irregulary pattern in retina and electron dense pigment granules scattered between the rhabdomes. Glia cell situated at the cell body of visual cell and glia cell process reached to rhabdomere portion. Below the rhabdome, tapetum were about $30{\mu}m$ distance from lens, which composed of 4-5 layers. It was about $25{\mu}m$ length that intermediate segment of distal portion of visual cell. Electron dense pigment granules between the intermediate segment were observed.

  • PDF

Embryology of Jeffersonia dubia Baker et S. Moore (Berberidaceae) and comparison with allied genera (깽깽이풀의 발생과 근연속간 비교)

  • Ghimire, Balkrishna;Heo, Kweon
    • Korean Journal of Plant Taxonomy
    • /
    • v.42 no.4
    • /
    • pp.260-266
    • /
    • 2012
  • Because the embryological features of Jeffersonia dubia are poorly understood, we conducted the first embryological study comparing it to other related genera of Berberidaceae. Important embryological features of J. dubia are as follows: the anther is tetrasporangiate, anther wall formation confirms basic type, glandular tapetum cells are two nucleate, the epidermis persistent, and the endothecium develops fibrous thickenings, anther dehiscence by two valves, meiosis in a microspore mother cell is accompanied by simultaneous cytokinesis, microspore tetrads are usually tetrahedral, pollen grains two cells at the time of anthesis. The ovule is bitegmic, anatropous and crassinucellate, archesporium single celled, development of the embryo sac Polygonum type, a mature embryo sac is ellipsoidal in shape. Endosperm formation is of Nuclear type and embryogeny Onagrad type. Seeds are arillate and seed coat exotestal type. Embryological comparisons showed that Jeffersonia resemble to Epimedium and Vancouveria rather than Berberis and Mahonia in some features, like as number of tapetal cells, cytokinesis in meiosis, and thickness of exotesta. It also resembles to Gymnospermium in mode of anther wall formation, number of tapetal cells, formation of nucellar cap, and nature of antipodal cells. Nevertheless, Jeffersonia and Gymnospermium differ from several other embryological features and molecular data too. Therefore, embryological evidences support that Jeffersonia is closely related with Epimedium and Vancouveria.

Microsporogenesis of Hibiscus syriacus L and Its Sporoderm Differentiation (무궁화의 화분형성 및 화분벽의 분화발달)

  • 김인선
    • Journal of Plant Biology
    • /
    • v.38 no.1
    • /
    • pp.95-105
    • /
    • 1995
  • Complete microsporogenesis of Hibiscus syriacus L. were carried out employing LM, TEM, and SEM to investigate the pollen ontogeny that undergoes considerable structural differentiation. The process first began with several cell diYisions in the anther primordium that produces 3 different tissues of epidennal, archesporial, and connective tissues. Only archesporial tissue involved further differentiation into the tapetum and formation of reproductive cells, pollen mother cells (PMC). The tapetum and PMC were closely associated with each other structurally and metabolically by exhibiting numerous plasmodesmata, mitochondria, and many small vacuoles in their dense cytoplasm. A callosic wall began to surround the PMC while meiosis took place in the PMC to produce 4 microspores. When thick callose encircled each microspore as a frame, the sporodenn development initiated from the plasma membrane of a pollen grain in a tetrad. The first fonned sporoderm layer was bacules and tectum of sexine that originated from the plasma membrane. After the dissolution of a callose, further development Qf sporoderm continued in the order of nexine 1, nexine 2, and intine layer. The nexine layer was thicker (ca. $2-3.5\;\mu\textrm{m}$) than the intine layer whose thickness was about $0.9-1.5\;\mu\textrm{m}$. Upon completion of the sporoderm development, that is after intine formation, spines and apertures of pollen surface ornamentation initiated from the tectum. Spines were dimorphic, about $4-9\;\mu\textrm{m}\;an;15-20\;\mu\textrm{m}$ in length, and no basal cushion was detected. The mature pollen grains ranged $100-200\;\mu\textrm{m}$ in diameter, but their average was about $170\;\mu\textrm{m}$. About 120 spines were observed over the spheroidal pollen surface. Apertures were simple punctures of $2-3\;\mu\textrm{m}$ in diameter and about 50 apertures were arranged somewhat helically over the surface. Comparing such features of form and size of the pollen, sporodenn sculpture and structure, and aperture and spine conditions with known evolutionary trends in the genus Hibiscus, Hibiscus syriacus seemed to possess many advanced features in the sporodenn differentiation.iation.

  • PDF

Expressional Patterns of Anther-specific Genes from Chinese Cabbage during the Flower Development (배추 약 발달 시기별 유전자의 발현 양상)

  • Kim, Hyun Uk;Chung, Kyu Hwan
    • Horticultural Science & Technology
    • /
    • v.17 no.1
    • /
    • pp.7-10
    • /
    • 1999
  • This study was carried out with the purpose of looking into the transcriptionally regulated genes related to the anther development, characterizing them, and applying their promoters to induce male-sterile plants and restore their fertility. Fifteen anther-specific clones were isolated from the anther cDNA library of Chinese cabbage through the differential screening and sequenced partially at both ends. These partial sequence data showed that cDNA clones BAN52, 84, 101, and 229 are very similar to polygalacturonase, ascorbate oxidase, $H^+-translocating$ ATPase, and pectin esterase genes respectively. However, the other clones have not been matched to any of gene sequences in data bank. In northern dot blot analysis, the transcripts of cDNA clone BAN5, 10, 33, 52, 57, 102, 103, 215, 229 appeared in the flower bud of 2.1 mm in length and their amounts were gradually increased along with the anther development. Transcription of cDNA clone BAN32, 54, 62, 84, 101 began in flower bud of 3.9 mm, which is the late stage in anther development. However, the transcription of BAN87 was very small, but its transcript was detected in all anther developmental stages.

  • PDF

Embryology of Gymnospermium microrrhynchum (Berberidaceae) (한계령풀의 생식기관 발생형태)

  • Ghimire, Balkrishna;Shin, Dong-Yong;Heo, Kweon
    • Korean Journal of Plant Taxonomy
    • /
    • v.40 no.4
    • /
    • pp.226-233
    • /
    • 2010
  • An intensive study of the embryology of Gymnospermium microrrhynchum was conducted to provide information regarding a discussion of the phylogenetic relationships of the genus, which is yet unstudied. Our results indicated that Gymnospermium is similar to other genera of Berberidaceae in terms of its embryological features. Nevertheless, newly reported and unique features are the well-developed endothelium and the undifferentiated seed coat type. Until the study of Gymnospermium, it may have been considered to be closer to Caulophyllum and Leontice in the tribe Leonticeae. These three genera share many morphological features as well as molecular similarities, by which they are kept in the same tribe, Leonticeae. However, very little detailed embryological data regarding these genera have been published thus far. Gymnospermium was characterized according to the basic type of anther wall formation as well as its glandular tapetum, successive cytokinesis in the microspore mother cell, two-celled mature pollen grains, anatropous and crassinucellate ovules with a nucellar cap, well-developed endothelium, its Polygonum type of embryo sac formation, its nuclear type of endosperm formation, and its undifferentiated seed coat type. In comparison with Nandina, there are many differences, such as the dehiscence of the anther, the cytokinesis in the microspore mother cells, the shape of the megaspore dyad, and the seed characteristics. Although we had no available detailed embryological information regarding Caulophyllum and Leontice, which are genera that are more closely related to Gymnospermium, we could deduce from the phylogenetic relationship that Gymnospermium, Caulophyllum, and Leontice are more closely related to each other than other genera of Berberidaceae on the basis of the seed characteristics.

Fine Structural Analysis of Principal and Secondary Eyes in Wandering Spider, Pardosa astrigera (배회성 거미 (Pardosa astrigera) 주안과 부안의 미세구조적 분석)

  • Jeong, Moon-Jin;Lim, Do-Seon;Moon, Myung-Jin
    • Applied Microscopy
    • /
    • v.30 no.1
    • /
    • pp.1-9
    • /
    • 2000
  • The wandering spider, Pardosa astrigera, had four pairs of ocelli that arranged in three rows on the cephalothorax. Along the anterior margin lay a pair of small anterior median (AM) eye flanked on each side by anterior lateral (AL) eye. Two large posterior median (PM) eye was situated on the clypeus behind the anterior row and still more posteriorly was a pair of posterior lateral (PL) eye. The visual cell of retina consisted of cell body, rhabdome, and intermediate segment. Bipolar neuron was found in anterior median eye (principal eye) and unipolar neuron in others (secondary eye). Rhabdome showed that arranged in PMeye and PLeye. But rhabdomes of AMeye and ALeye were irregular in retina. Except AMeye, incontinuous tapetum found in ALeye, PMeye, PLeye. Anterior median eye was similar to anterior lateral eye in length and posterior median eye similar to posterior lateral eye. Component size of eye were similar to 4 pairs eye in cornea. Size of lens, cell body, and rhabdome was similar not only anterior median eye and anterior lateral eye but also posterior median eye and posterior lateral eye. Vitreous body was large posterior median eye than others.

  • PDF

Recent Advances in the Studies of Self-Incompatibility of plants (식물의 자가불화합성, 최근의 진보)

  • 한창열;한지학
    • Korean Journal of Plant Tissue Culture
    • /
    • v.21 no.5
    • /
    • pp.253-275
    • /
    • 1994
  • Many flowering plants possess genetically controlled self -incompatibility (SI) system that prevents inbreeding and promotes outcrosses. SI is usually controlled by a single, multiallelic S-locus. In gametophytically controlled system, SI results when the S-allele of the pollen is matched by one of the two S-alleles in the style, while in the sporophytic system self-incompatible reaction occurs by the interaction between the pistil genotype and genotype of, not the pollen, but the pollen parent In the former system the self-incompatible phenotype of pollen is determined by the haploid genome of the pollen itself but in the latter the pollen phenotype is governed by the genotype of the pollen parent along with the occurrence of either to-dominant or dominant/recessive allelic interactions. In the sporophytic type the inhibition reaction occurs within minutes following pollen-stigma contact, the incompatible pollen grains usually failing to germinate, whereas in gametophytic system pollen tube inhibition takes place during growth in the transmitting tissue of the style. Recognition and rejection of self pollen are the result of interaction between the S-locus protein in the pistil and the pollen protein. In the gametophytic SI the S-associated glycoprotein which is similar to the fungal ribonuclease in structure and function are localized at the intercellular matrix in the transmitting tissue of the style, with the highest concentration in the collar of the stigma, while in the sporophytic SI deposit of abundant S-locus specific glycoprotein (SLSG).is detected in the cell wall of stigmatic papillae of the open flowers. In the gametophytic system S-gene is expressed mostly at the stigmatic collar the upper third of the style length and in the pollen after meiosis. On the other hand, in the sporophytic SI S-glycoprotein gene is expressed in the papillar cells of the stigma as well as in e sporophytic tape is cells of anther wall. Recognition and rejection of self pollen in the gametophytic type is the reaction between the ribonuclease in the transmitting tissue of the style and the protein in the cytoplasm of pollen tube, whereas in the sporophytic system the inhibition of selfed pollen is caused by the interaction between the Sycoprotein in the wall of stigmatic papillar cell and the tapetum-origin protein deposited on the outer wall of the pollen grain. The claim that the S-allele-associated proteins are involved in recognition and rejection of self pollen has been made merely based on indirect evidence. Recently it has been verified that inhibition of synthesis of S$_3$ protein in Petunia inflata plants of S$_2$S$_3$ genotype by the antisense S$_3$ gene resulted in failure of the transgenic plant to reject S$_3$ pollen and that expression of the transgenic encoding S$_3$ protein in the S$_1$S$_2$ genotype confers on the transgenic plant the ability to reject S$_3$ pollen. These finding Provide direct evidence that S-proteins control the s elf-incompatibility behavior of the pistil.

  • PDF