Protein Targeting to the Nuclear Pore. What Can We Learn from Plants?1

Smith, Harley M. S.; Raikhel, Natasha V.

doi:10.1104/pp.119.4.1157

Cited by 50 publications

(26 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…But the presence of Al in high amounts at the nuclear membrane could interfere with numerous activities such as microtubule binding at the membrane surface during the G2 phase of the cell cycle (Franklin and Cande, 1999) and protein recognition, binding, and transport into the nucleus (Smith and Raikhel, 1999). With thick tissue sections such as those used here, it is not possible to determine how much Al accumulated inside the nucleus.…”

Section: Discussionmentioning

confidence: 94%

Aluminum Accumulation at Nuclei of Cells in the Root Tip. Fluorescence Detection Using Lumogallion and Confocal Laser Scanning Microscopy

Silva¹,

Smyth²,

Moxley³

et al. 2000

Plant Physiology

146

View full text Add to dashboard Cite

The mechanistic basis for Al toxicity effects on root growth is still a matter of speculation, but it almost certainly involves decreased cell division at the root apex. In this series of experiments, we attempt to determine whether Al enters meristematic cells and binds to nuclei when roots are exposed to a low Al 3ϩ activity in solution. The methodology involved the use of the Al-sensitive stain lumogallion (3-[2,4 dihydroxyphenylazo]-2-hydroxy-5-chlorobenzene sulfonic acid), the DNA stain 4Ј,6-diamino-phenylindole, and confocal laser scanning microscopy. Soybean (Glycine max L. Merr.) cv Young (Al-sensitive) and PI 416937 (Al-tolerant) genotypes were exposed to 1.45 m Al 3ϩ for periods ranging from 30 min to 72 h, and then washed with 10 mm citrate to remove apoplastic Al. Fluorescence images show that within 30 min Al entered cells of the sensitive genotype and accumulated at nuclei in the meristematic region of the root tip. Substantial Al also was present at the cell periphery. The images indicated that the Al-tolerant genotype accumulated lower amounts of Al in meristematic and differentiating cells of the root tip and their cell walls. Collectively, the results support an important role for exclusion in Al tolerance.

show abstract

Section: Discussionmentioning

confidence: 94%

Aluminum Accumulation at Nuclei of Cells in the Root Tip. Fluorescence Detection Using Lumogallion and Confocal Laser Scanning Microscopy

Silva¹,

Smyth²,

Moxley³

et al. 2000

Plant Physiology

146

View full text Add to dashboard Cite

show abstract

“…Although the mechanism of nuclear transport in plants has not been intensively studied, it is likely to be similar to the mechanism that has been described in other organisms (Merkle, 2001;Smith and Raikhel, 1999). Proper localization of proteins in plant cells depends on the same type of nuclear localization signal (Hicks and Raikhel, 1995) and nuclear export sequence (Haasen et al, 1999;Ward and Lazarowitz, 1999) that fulfill this function in other organisms.…”

Section: Introductionmentioning

confidence: 93%

HASTY, theArabidopsisortholog of exportin 5/MSN5, regulates phase change and morphogenesis

et al. 2003

View full text Add to dashboard Cite

Loss-of-function mutations of HASTY (HST) affect many different processes in Arabidopsis development. In addition to reducing the size of both roots and lateral organs of the shoot, hstmutations affect the size of the shoot apical meristem, accelerate vegetative phase change, delay floral induction under short days, adaxialize leaves and carpels, disrupt the phyllotaxis of the inflorescence, and reduce fertility. Double mutant analysis suggests that HST acts in parallel toSQUINT in the regulation of phase change and in parallel toKANADI in the regulation of leaf polarity. Positional cloning demonstrated that HST is the Arabidopsis ortholog of the importin β-like nucleocytoplasmic transport receptors exportin 5in mammals and MSN5 in yeast. Consistent with a potential role in nucleocytoplasmic transport, we found that HST interacts with RAN1 in a yeast two-hybrid assay and that a HST-GUS fusion protein is located at the periphery of the nucleus. HST is one of at least 17 members of the importin-βfamily in Arabidopsis and is the first member of this family shown to have an essential function in plants. The hst loss-of-function phenotype suggests that this protein regulates the nucleocytoplasmic transport of molecules involved in several different morphogenetic pathways, as well as molecules generally required for root and shoot growth.

show abstract

“…The GFP-tagging approach has been used widely to study the subcellular locations of various proteins (Zuo et al, 2000;Hall and Cannon, 2002). In addition, it is known that the nuclear targeting of a protein is dictated by nuclear localization signals that are rich in basic amino acids and that are position independent (Smith and Raikhel, 1999).…”

Section: Fra1 Protein Localizationmentioning

confidence: 99%

A Kinesin-Like Protein Is Essential for Oriented Deposition of Cellulose Microfibrils and Cell Wall Strength

et al. 2002

View full text Add to dashboard Cite

Cortical microtubules have long been hypothesized to regulate the oriented deposition of cellulose microfibrils. However, the molecular mechanisms of how microtubules direct the orientation of cellulose microfibril deposition are not known. We have used fibers in the inflorescence stems of Arabidopsis to study secondary wall deposition and cell wall strength and found a fragile fiber ( fra1 ) mutant with a dramatic reduction in the mechanical strength of fibers. The fra1 mutation did not cause any defects in cell wall composition, secondary wall thickening, or cortical microtubule organization in fiber cells. An apparent alteration was found in the orientation of cellulose microfibrils in fra1 fiber walls, indicating that the reduced mechanical strength of fra1 fibers probably was attributable to altered cellulose microfibril deposition. The FRA1 gene was cloned and found to encode a kinesin-like protein with an N-terminal microtubule binding motor domain. The FRA1 protein was shown to be concentrated around the periphery of the cytoplasm but absent in the nucleus. Based on these findings, we propose that the FRA1 kinesin-like protein is involved in the microtubule control of cellulose microfibril order.

show abstract

Protein Targeting to the Nuclear Pore. What Can We Learn from Plants?1

Cited by 50 publications

References 39 publications

Aluminum Accumulation at Nuclei of Cells in the Root Tip. Fluorescence Detection Using Lumogallion and Confocal Laser Scanning Microscopy

Aluminum Accumulation at Nuclei of Cells in the Root Tip. Fluorescence Detection Using Lumogallion and Confocal Laser Scanning Microscopy

HASTY, theArabidopsisortholog of exportin 5/MSN5, regulates phase change and morphogenesis

A Kinesin-Like Protein Is Essential for Oriented Deposition of Cellulose Microfibrils and Cell Wall Strength

Contact Info

Product

Resources

About