PLK1 controls centriole distal appendage formation and centrobin removal via independent pathways

Trisporella beccariana comb.nov. is redescribed from decomposing leaf petiole (or rachis) bases of Nypa fruticans recently collected in Malaysia and the Philippines. The superficial ascomata bear bitunicate asci with (3–)5(–7)-septate ascospores that are brown and verrucose, except for the prominent hyaline basal cell, and furnished with a distinctive apical appendage that arises from the spore wall. The ultrastructure of the fungus is contrasted with that of species of Corollospora and Corallicola, with particular reference to the mode of ascospore appendage formation. The species was originally described from a Sarawak collection as Sphaeria beccariana and later transferred to Melanomma and given the new name Melanomma cesatianum. Gibberidea nipae is a synonym. The recent collections were compared with type specimens. The fungus is not properly placed in Melanomma or Gibberidea or other known genera and a new genus Tirisporella is described. Keywords: Ascomycotina, ascospore appendage, mangrove fungus, taxonomy, ultrastracture.

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Divergent and conserved roles of extradenticle in body segmentation and appendage formation, respectively, in the cricket Gryllus bimaculatus

Developmental Biology ◽

10.1016/j.ydbio.2007.09.060 ◽

2008 ◽

Vol 313 (1) ◽

pp. 67-79 ◽

Cited By ~ 24

Author(s):

Taro Mito ◽

Monica Ronco ◽

Tomohiro Uda ◽

Taro Nakamura ◽

Hideyo Ohuchi ◽

...

Keyword(s):

Gryllus Bimaculatus ◽

Body Segmentation ◽

Appendage Formation

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295 The Effect of Cultivar, GA4+7, and Number of Fruit per Spur on Flower Initiation in Apple

HortScience ◽

10.21273/hortsci.34.3.493c ◽

1999 ◽

Vol 34 (3) ◽

pp. 493C-493

Author(s):

Emily Hoover ◽

S. McArtney ◽

S. Tustin ◽

M. White ◽

P. Hirst

Keyword(s):

Flower Initiation ◽

Leaf Fall ◽

Full Bloom ◽

Flower Bud ◽

Biennial Bearing ◽

Appendage Formation ◽

Commercial Crop ◽

Bud Initiation ◽

Number Of Seeds

Experiments were initiated to document the effect of cultivar, GA4+7, and number of fruit/spur on appendage number and flower bud initiation in apple. `Pacific Rose' is strongly biennial, `Braeburn' and `Fuji' are moderately biennial, and `Royal Gala' is not biennial. In the cultivar study, buds were sampled every 18 days starting at 50 days after full bloom and continuing through until leaf fall to determine the rate of appendage formation and appendage number in relation to doming. Because of the tendency for `Pacific Rose' to exhibit biennial bearing, the rate of appendage formation and the timing of doming were compared on nonfruiting trees, trees carrying a commercial crop, and trees sprayed with 300 PPM GA4+7 applied 14 days after full bloom. Number of appendages for the treatments were similar up to 100 days after full bloom. Presence of fruit on a spur has been demonstrated to inhibit flowering of apple. Spurs of `Pacific Rose', `Splendor', and `Royal Gala' were labeled with zero, one, two, and three fruit per spur and sampled three times during the season. As buds were harvested to count appendage number, the number of fruit per spur and the number of total seeds per spur were recorded. Correlation between number of seeds per spur and rate of appendage formation were done.

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A ciliopathy complex builds distal appendages to initiate ciliogenesis

The Journal of Cell Biology ◽

10.1083/jcb.202011133 ◽

2021 ◽

Vol 220 (9) ◽

Author(s):

Dhivya Kumar ◽

Addison Rains ◽

Vicente Herranz-Pérez ◽

Quanlong Lu ◽

Xiaoyu Shi ◽

...

Keyword(s):

Early Step ◽

Appendage Formation ◽

Distal Centriole

Cells inherit two centrioles, the older of which is uniquely capable of generating a cilium. Using proteomics and superresolved imaging, we identify a module that we term DISCO (distal centriole complex). The DISCO components CEP90, MNR, and OFD1 underlie human ciliopathies. This complex localizes to both distal centrioles and centriolar satellites, proteinaceous granules surrounding centrioles. Cells and mice lacking CEP90 or MNR do not generate cilia, fail to assemble distal appendages, and do not transduce Hedgehog signals. Disrupting the satellite pools does not affect distal appendage assembly, indicating that it is the centriolar populations of MNR and CEP90 that are critical for ciliogenesis. CEP90 recruits the most proximal known distal appendage component, CEP83, to root distal appendage formation, an early step in ciliogenesis. In addition, MNR, but not CEP90, restricts centriolar length by recruiting OFD1. We conclude that DISCO acts at the distal centriole to support ciliogenesis by restraining centriole length and assembling distal appendages, defects in which cause human ciliopathies.

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PLK1 controls centriole distal appendage formation and centrobin removal via independent pathways

10.1101/2021.07.06.451279 ◽

2021 ◽

Author(s):

Morgan LeRoux-Bourdieu ◽

Daniela Harry ◽

Patrick Meraldi

Keyword(s):

Epithelial Cells ◽

S Phase ◽

Structural Elements ◽

Human Epithelial Cells ◽

Appendage Formation

Centrioles are central structural elements of centrosomes and cilia. They originate as daughter centrioles from existing centrioles in S-phase and reach their full functionality with the formation of distal and subdistal appendages two mitoses later. Current models postulate that the centriolar protein centrobin acts as placeholder for distal appendage proteins that must be removed to complete distal appendage formation. Here, we investigated in non-transformed human epithelial cells the mechanisms controlling centrobin removal and its effect on distal appendage formation. We demonstrate that centrobin is removed from older centrioles due to a higher affinity for the newly born daughter centrioles, under the control of the centrosomal kinase Plk1. Centrobin removal also depends on the presence of subdistal appendage proteins on the oldest centriole. It is, however, not required for distal appendage formation even though this process is equally dependent on Plk1. We conclude that during centriole maturation, Plk1 kinase regulates centrobin removal and distal appendage formation via separate pathways.

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The development of a biological novelty: a different way to make appendages as revealed in the snout of the star-nosed mole Condylura cristata

Journal of Experimental Biology ◽

10.1242/jeb.202.20.2719 ◽

1999 ◽

Vol 202 (20) ◽

pp. 2719-2726

Author(s):

K.C. Catania ◽

R.G. Northcutt ◽

J.H. Kaas

Keyword(s):

Body Wall ◽

Developmental Process ◽

Deep Layer ◽

The Body ◽

Embryonic Stage ◽

Unique Pattern ◽

Appendage Development ◽

The Face ◽

Appendage Formation ◽

Condylura Cristata

The nose of the star-nosed mole Condylura cristata is a complex biological novelty consisting of 22 epidermal appendages. How did this new set of facial appendages arise? Recent studies find remarkable conservation of the genes expressed during appendage formation across phyla, suggesting that the basic mechanisms for appendage development are ancient. In the nose of these moles, however, we find a unique pattern of appendage morphogenesis, showing that evolution is capable of constructing appendages in different ways. During development, the nasal appendages of the mole begin as a series of waves in the epidermis. A second deep layer of epidermis then grows under these superficial epidermal waves to produce 22 separate, elongated epidermal cylinders embedded in the side of the mole's face. The caudal end of each cylinder later erupts from the face and rotates forward to project rostrally, remaining attached only at the tip of the snout. As a result of this unique ‘unfolding’ formation, the rostral end of each adult appendage is derived from caudal embryonic facial tissue, while the caudal end of each appendage is derived from rostral facial tissue. This developmental process has essentially no outgrowth phase and results in the reversal of the original embryonic orientation of each appendage. This differs from the development of other known appendages, which originate either as outgrowths of the body wall or from subdivisions of outgrowths (e.g. tetrapod digits). Adults of a different mole species (Scapanus townsendii) exhibit a star-like pattern that resembles an embryonic stage of the star-nosed mole, suggesting that the development of the star recapitulates stages of its evolution.

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Developmental regulatory mechanisms in the evolution of insect diversity

Development ◽

10.1242/dev.1994.supplement.217 ◽

1994 ◽

Vol 1994 (Supplement) ◽

pp. 217-223

Author(s):

Sean B. Carroll

Keyword(s):

Genetic Basis ◽

Target Genes ◽

Genetic Regulation ◽

Morphological Diversity ◽

Fruit Fly ◽

Color Pattern ◽

Fruit Flies ◽

Distinct Pattern ◽

Homeotic Genes ◽

Appendage Formation

The major architectural differences between most Arthropod classes and orders involve variations in the number, type and pattern of body appendages. We have utilized the emerging knowledge of appendage formation in fruit flies to begin to address the developmental and genetic basis of morphological diversity among insects. Butterflies, for example, differ from fruit flies in possessing larval abdominal limbs, two pairs of adult wings, and a sophisticated system of wing color pattern formation. We have found that the genetic bases for these three major morphological features involve differences between flies and butterflies at three levels of genetic regulation during development. First, we show that the presence of abdominal limbs in butterflies is associated with striking changes in the regulation of specific homeotic genes in the abdominal segments of the butterfly embryo. Second, we suggest that the two-winged state of the fruit fly and the distinct pattern of the butterfly hindwing are the consequence of many accurrulated changes in the target genes regulated by the Ultrabithorax homeotic gene. And finally, we demonstrate that a new genetic program, involving many of the same genes that specify the conserved global patterning coordinates of fruit fly and butterfly wings, has been superimposed onto the butterfly wing to create their unique color patterning system. These findings demonstrate how morphological diversity arises from the different ways in which conserved sets of regulatory genes are deployed during development.

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