Acid invertase is predominantly localized to cell walls of both the practically symplasmically isolated sieve element/companion cell complex and parenchyma cells in developing apple fruits

Zhang, D. P.; Lu, Yingzhi; Wang, Y. Z.; Duan, Chongwen; Yan, Hao

doi:10.1046/j.0016-8025.2001.00720.x

Cited by 51 publications

(60 citation statements)

References 67 publications

(127 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…are consistent with those previously reported (Zhang et al, 2001b). In the major bundle, the plasmodesmal density and frequency become null at the late stage of fruit development, whereas in the minor bundle they are null throughout the fruit developmental process (Table I).…”

Section: Structurally Symplasmic Isolation Of Se-cc Complexsupporting

confidence: 82%

“…The predominantly cell wall-localization of invertases (Zhang et al, 2001b) is also in agreement with an apoplasmic phloem unloading pathway in this fruit. Postphloem transport may occur by simultaneous apo-and symplasmic pathways, as indicated by the plasma membrane-located putative monosaccharide transporter in the PCs (Fig.…”

Section: Possible Mechanism Of Phloem Unloading In Apple Fruitsupporting

confidence: 57%

“…1A). Our previous investigation, which concerned only the major sepal bundle, showed that the plasmodesmatal frequency between the SE-CC complex and its adjacent cells was low in the major bundle at the early stage of fruit development (Zhang et al, 2001b). The present study shows that the major and minor sepal bundles differ in both their size and structure with more vascular strands and xylem vessels in the major than in the minor bundles (Fig.…”

Section: Structurally Symplasmic Isolation Of Se-cc Complexmentioning

confidence: 99%

“…The method described by Zhang et al (2001b) was used. The vascular bundle zone (sepal bundles including major and minor bundles; Fig.…”

Section: Tissue Preparation For Structural Observationmentioning

confidence: 99%

“…Specimen preparation and immunogold labeling were conducted essentially according to Zhang et al (2001b). The following procedures were carried out at 4°C unless otherwise stated.…”

Section: Immunogold Labelingmentioning

confidence: 99%

See 4 more Smart Citations

Evidence for Apoplasmic Phloem Unloading in Developing Apple Fruit

et al. 2004

View full text Add to dashboard Cite

The phloem unloading pathway remains unclear in fleshy fruits accumulating a high level of soluble sugars. A structural investigation in apple fruit (Malus domestica Borkh. cv Golden Delicious) showed that the sieve element-companion cell complex of the sepal bundles feeding the fruit flesh is symplasmically isolated over fruit development. 14 C-autoradiography indicated that the phloem of the sepal bundles was functional for unloading. Confocal laser scanning microscopy imaging of carboxyfluorescein unloading showed that the dye remained confined to the phloem strands of the sepal bundles from the basal to the apical region of the fruit. A 52-kD putative monosaccharide transporter was immunolocalized predominantly in the plasma membrane of both the sieve elements and parenchyma cells and its amount increased during fruit development. A 90-kD plasma membrane H 1 -ATPase was also localized in the plasma membrane of the sieve element-companion cell complex. Studies of [ 14 C]sorbitol unloading suggested that an energy-driven monosaccharide transporter may be functional in phloem unloading. These data provide clear evidence for an apoplasmic phloem unloading pathway in apple fruit and give information on the structural and molecular features involved in this process.The partitioning of sugars in economically important sink organs such as fruits or seeds is governed by several complex physiological processes, including photosynthetic rate, phloem loading in the source leaf, long-distance translocation in the phloem, phloem unloading in sink organs, postphloem transport, and metabolism of imported sugars in sink cells (Oparka, 1990;Patrick, 1997). It is now well accepted that phloem unloading plays a key role in the partitioning of photoassimilate (Fisher and Oparka, 1996;Patrick, 1997;Viola et al., 2001). The process of phloem unloading has been studied extensively over the last 20 years (for review, see Oparka, 1990;Patrick, 1997;Schulz, 1998) but still remains poorly understood. Elucidation of the cellular pathway of phloem unloading is central to this process, because, to a large extent, the unloading path determines the key transport events responsible for assimilate movement from the sieve elements (SEs) to the recipient sink cells (Fisher and Oparka, 1996;Patrick, 1997). A symplasmic phloem unloading pathway predominates in most sink tissues such as vegetative apices (Oparka et al., 1995;Patrick, 1997;Imlau et al., 1999), sink leaves (Roberts et al., 1997;Imlau et al., 1999;Haupt et al., 2001), and potato tubers that represent a typical terminal vegetative storage sink (Oparka and Santa Cruz, 2000;Viola et al., 2001). Symplasmic unloading is also efficient in the maternal tissues of developing seeds that represent a class of terminal reproductive storage sinks (Ellis et al., 1992;Patrick et al., 1995;Wang et al., 1995a;Patrick, 1997), although transfer of solutes to the apoplasm may occur at some point along the postphloem pathway (Patrick, 1997). In some cases, symplasmic unloading also occurs in elongating z...

show abstract

Section: Structurally Symplasmic Isolation Of Se-cc Complexsupporting

confidence: 82%

Section: Possible Mechanism Of Phloem Unloading In Apple Fruitsupporting

confidence: 57%

Section: Structurally Symplasmic Isolation Of Se-cc Complexmentioning

confidence: 99%

“…The method described by Zhang et al (2001b) was used. The vascular bundle zone (sepal bundles including major and minor bundles; Fig.…”

Section: Tissue Preparation For Structural Observationmentioning

confidence: 99%

“…Specimen preparation and immunogold labeling were conducted essentially according to Zhang et al (2001b). The following procedures were carried out at 4°C unless otherwise stated.…”

Section: Immunogold Labelingmentioning

confidence: 99%

See 3 more Smart Citations

Evidence for Apoplasmic Phloem Unloading in Developing Apple Fruit

et al. 2004

View full text Add to dashboard Cite

show abstract

Ammonia stress on the carbon metabolism of Ceratophyllum demersum

Gao

et al. 2015

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

In the present study, carefully controlled pH ranges (7 and 9) were used to distinguish between the effects of un-ionized NH3 and the NH4 (+) ion. The objective was to find the effect of different total ammonia nitrogen concentrations and pH values on the carbon metabolism of Ceratophyllum demersum. The authors investigated the effects of ammonia on the nonstructural carbohydrate content in shoots of C. demersum. Ammonia treatment decreased the contents of nonstructural carbohydrate, soluble sugar, sucrose, fructose, and starch in leaves. Meanwhile, increasing the pH value exacerbated the decline of the C. demersum nonstructural carbohydrate content. In addition, the activity of invertase was increased during the experiment. These results suggest that ammonia severely inhibits plant growth by disturbing nonstructural carbohydrate content. It has been suggested that ammonia has toxic effects on C. demersum and that the higher the pH in water, the more obvious the physiological responses that C. demersum exhibits. The results of the present study can provide some reference for studying the living conditions of submersed macrophytes under the stress of NH3.

show abstract

Comparative proteomic analysis reveals similar and distinct features of proteins in dry and wet stigmas

Sang¹,

Xu²,

Fang³

et al. 2012

Proteomics

View full text Add to dashboard Cite

Angiosperm stigma supports compatible pollen germination and tube growth, resulting in fertilization and seed production. Stigmas are mainly divided into two types, dry and wet, according to the absence or presence of exudates on their surfaces. Here, we used 2DE and MS to identify proteins specifically and preferentially expressed in the stigmas of maize (Zea Mays, dry stigma) and tobacco (Nicotiana tabacum, wet stigma), as well as proteins rinsed from the surface of the tobacco stigma. We found that the specifically and preferentially expressed proteins in maize and tobacco stigmas share similar distributions in functional categories. However, these proteins showed important difference between dry and wet stigmas in a few aspects, such as protein homology in "signal transduction" and "lipid metabolism," relative expression levels of proteins containing signal peptides and proteins in "defense and stress response." These different features might be related to the specific structures and functions of dry and wet stigmas. The possible roles of some stigma-expressed proteins were discussed. Our results provide important information on functions of proteins in dry and wet stigmas and reveal aspects of conservation and divergence between dry and wet stigmas at the proteomic level.

show abstract

Acid invertase is predominantly localized to cell walls of both the practically symplasmically isolated sieve element/companion cell complex and parenchyma cells in developing apple fruits

Cited by 51 publications

References 67 publications

Evidence for Apoplasmic Phloem Unloading in Developing Apple Fruit

Evidence for Apoplasmic Phloem Unloading in Developing Apple Fruit

Ammonia stress on the carbon metabolism of Ceratophyllum demersum

Comparative proteomic analysis reveals similar and distinct features of proteins in dry and wet stigmas

Contact Info

Product

Resources

About