Tapetal Ultrastructural Changes During Pollen Development. I. Studies on<i>Antirrhinum Maius</i>

Lombardo, Giuliana; Carraro, Luisa

doi:10.1080/00087114.1976.10796654

Cited by 25 publications

(8 citation statements)

References 21 publications

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“…One of the hallmarks of most secreted proteins is the presence of a short cleavable signal peptide which directs the nascent protein into the endoplasmic reticulum from whence it is processed via the Golgi apparatus. It has been reported that cytoplasmic lipid bodies in some of the Brassicaceae may also be secreted from tapetal cells prior to their lysis (Lombardo and Carraro, 1976;Owen and Makaroff, 1995). In the present study we found that a locular extract from gently disrupted anthers of B. napus contained a low density lipidic fraction containing 45-48 kDa oleosin-like proteins.…”

Section: Subcellular Targeting Of Oleosin-like Proteinssupporting

confidence: 61%

Biosynthesis, targeting and processing of oleosin‐like proteins, which are major pollen coat components in Brassica napus

Murphy,

Ross

1998

The Plant Journal

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SummaryThe purpose of this study is to characterise the biosynthesis, targeting and processing of some of the major protein components of the pollen coat, or tryphine, of Brassica napus. The authors have N‐terminally sequenced 11 of the most abundant pollen coat polypeptides, and nine of these sequences correspond to proteolytically cleaved products of seven oleosin‐like genes, i.e. Oln B;1 to Oln B;6 and Oln B;11. The Oln B;11 gene product is co‐ or post‐translationally targeted in vitro to canine microsomal membranes. This implies that the oleosin‐like protein is targeted to the endoplasmic reticulum in tapetal cells in vivo. Affinity‐purified antibodies raised against a 20‐residue domain of Oln B;3 and B;4 gene products cross‐reacted with full‐length proteins of 45–48 kDa in early developing (< 2 mm to 5 mm) buds and anthers, but recognised truncated proteins of 32–38 kDa at later (4 mm to 7 mm) stages of development. The 45–48 kDa immunoreactive proteins were associated with a floating lipid body fraction obtained from a tapetal/locular fluid extract from maturing anthers and a major 48 kDa polypeptide from this fraction was confirmed by N‐terminal sequencing to be a full length product of the Oln B;3 gene. Quantitative immunocytochemical studies showed that the full length 45–48 kDa oleosin‐like proteins were specifically localised in the interior of tapetal cytoplasmic lipid bodies where they were associated with a regular hexagonal‐like fibrous reticulum. No significant labelling of elaioplasts was observed. The same antibodies specifically labelled 32–38 kDa oleosin‐like proteins on the extracellular pollen coat of maturing pollen grains. These results demonstrate for the first time that many of the major pollen coat proteins are derived from an endoproteolytic cleavage of precursor oleosin‐like proteins that originally accumulate within the large cytoplasmic lipid bodies of tapetal cells.

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Section: Subcellular Targeting Of Oleosin-like Proteinssupporting

confidence: 61%

Biosynthesis, targeting and processing of oleosin‐like proteins, which are major pollen coat components in Brassica napus

Murphy,

Ross

1998

The Plant Journal

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“…K. Schum. of Malavaceae, and Canscora alata, Gentiana acaulis, and Swertia perennis L. of Gentianaceae (Lombardo and Carraro, 1976;Strittmatter and Galati, 2000;Vinckier and Smets, 2003;Galati et al, 2007). The occurrence of orbicules is also observed from the following extremely restricted taxa, with invasive tapetum type as the intermediate form of amoeboid and secretory types: Aechmea diclamydea Baker (Bromeliaceae), Quercus robur L. (Fagaceae), Modiolastrum malvifolium (Griseb.)…”

Section: Systematic Implication Of Orbicules and Their Relationship Tmentioning

confidence: 96%

“…Walp., Acacia conferta, Benth. Beta vulgaris L., Butomus umbellatus L., Canscora alata (Roth) Wall., and Gentiana acaulis L., their correlation with the tapetum type remains unclear (Lombardo and Carraro, 1976;Fernando and Cass, 1994;Huysmans et al, 1998;Strittmatter and Galati, 2000;Vinckier and Smets, 2003;Furness, 2008;Taylor et al, 2008;Verstraete et al, 2014). Orbicules are readily observable in mature anther and inner locule wall by scanning electron microscopy (SEM).…”

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confidence: 99%

The phylogenetic potential of orbicules in angiosperms

문혜경¹

2018

Korean J. Pl. Taxon

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The distribution of orbicules was investigated for eleven taxa of six genera in Lamiaceae and four taxa of three genera in Verbenaceae using scanning electron microscopy. A literature survey to evaluate the phylogenetic potential of the orbicules and their possible correlations with tapetum types was also conducted. The orbicules are consistently absent in all investigated taxa of Lamiaceae, while small orbicules of an average size of less than 1 µm are densely distributed in Verbenaceae. In fact, orbicules appear consistently in 123 of 150 angiosperm families when investigated in at least one species. Thus, the distribution patterns of orbicules could be a useful diagnostic character in angiosperms. In addition, orbicules occur in 84% taxa of the secretory tapetum type, while they are commonly absent in the amoeboid tapetum type (ca. 80%). The presence of orbicules may be correlated with the secretory tapetum type. However, the study of orbicules is restricted in 150 families and the tapetum type within these families can be applied for 92 families out of a total of 416 angiosperm families. Thus, further investigation of orbicules is necessary in extended taxa to address the questions pertaining to orbicules.

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“…We undertook a series of studies on the developmental stages of the tapetal cells, particularly as regards the meaning and origin of the many vesicles found in the tapetum befor the beginning of meiosis. The first observations made on Antirrhinum maitts have been reported in a previous paper (LoMBARDO and CARRARO 1976). Here we report the results of our studies on Pelargonium zonale and Kalanchoe obtusa, characterized, like Antirrhinum maius, by a typical secretory tapetum.…”

Section: Introductionmentioning

confidence: 80%

Tapetal Ultrastructural Changes During Pollen Development. II. Studies onPelargonium ZonaleandKalanchoë Obtusa

Carraro

Lombardo

1976

Caryologia

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Tapetal Ultrastructural Changes During Pollen Development. I. Studies onAntirrhinum Maius

Cited by 25 publications

References 21 publications

Biosynthesis, targeting and processing of oleosin‐like proteins, which are major pollen coat components in Brassica napus

Biosynthesis, targeting and processing of oleosin‐like proteins, which are major pollen coat components in Brassica napus

The phylogenetic potential of orbicules in angiosperms

Tapetal Ultrastructural Changes During Pollen Development. II. Studies onPelargonium ZonaleandKalanchoë Obtusa

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