scholarly journals Molecular Cloning of Two Exo-β-glucanases and Their in vivo Substrates in the Cell Walls of Lily Pollen Tubes

2004 ◽  
Vol 45 (4) ◽  
pp. 436-444 ◽  
Author(s):  
Hiroyuki Takeda ◽  
Takuo Yoshikawa ◽  
Xi-Zhen Liu ◽  
Naoki Nakagawa ◽  
Yi-Qin Li ◽  
...  
PROTOPLASMA ◽  
1997 ◽  
Vol 200 (1-2) ◽  
pp. 87-98 ◽  
Author(s):  
S. Roy ◽  
K. J. Eckard ◽  
S. Lancelle ◽  
P. K. Hepler ◽  
E. M. Lord

2000 ◽  
Vol 67 (4) ◽  
pp. 585-596 ◽  
Author(s):  
SELVARANI GOVINDASAMY-LUCEY ◽  
PRAMOD K. GOPAL ◽  
PATRICK A. SULLIVAN ◽  
CHRISTOPHER J. PILLIDGE

The autolysin, N-acetyl muramidase (AcmA), of six commercial Lactococcus lactis subsp. cremoris starter strains and eight Lc. lactis subsp. cremoris derivatives or plasmid-free strains was shown by renaturing SDS-PAGE (zymogram analysis) to be degraded by the cell envelope proteinase (lactocepin; EC 3.4.21.96) after growth of strains in milk at 30 °C for 72 h. Degradation of AcmA was less in starter strains and derivatives producing lactocepin I/III (intermediate specificity) than in strains producing lactocepin I. This supports previous observations on AcmA degradation in derivatives of the laboratory strain Lc. lactis subsp. cremoris MG1363 (Buist et al. Journal of Bacteriology180 5947–5953 1998). In contrast to the MG1363 derivatives, however, the extent of autolysis in milk of the commercial Lc. lactis subsp. cremoris starter strains in this study did not always correlate with lactocepin specificity and AcmA degradation. The distribution of autolysins within the cell envelope of Lc. lactis subsp. cremoris starter strains and derivatives harvested during growth in milk was compared by zymogram analysis. AcmA was found associated with cell membranes as well as cell walls and some cleavage of AcmA occurred independently of lactocepin activity. An AcmA product intermediate in size between precursor (46 kDa) and mature (41 kDa) forms of AcmA was clearly visible on zymograms, even in the absence of lactocepin I activity. These results show that autolysis of commercial Lc. lactis subsp. cremoris starter strains is not primarily determined by AcmA activity in relation to lactocepin specificity and that proteolytic cleavage of AcmA in vivo is not fully defined.


2000 ◽  
Vol 125 (2) ◽  
pp. 265-270 ◽  
Author(s):  
A.M.S. Nyomora ◽  
P.H. Brown ◽  
K. Pinney ◽  
V.S. Polito

The effect of boron (B) on in vivo and in vitro development of almond [Prunus dulcis (Mill.) D.A. Webb (syn. P. amygdalus Batsch)] pollen and pollen tubes and the resultant effect on fruit set was studied in mature trees. The cultivars Mono (pistil donor) and Butte (pollinizer) in an orchard with low soil B in Fresno, California were sprayed with B at 0, 0.8, 1.7, or 2.5 kg·ha-1 during Fall 1993. Pollen viability as indicated by the fluorescein diacetate method (FDA) was >85% and was not affected by field-applied B, however, in vivo pollen germination and tube growth were enhanced by foliar-applied B. More effect of applied B on in vivo growth appeared as pollen tubes progressed toward the ovary. For in vitro germination, foliar-applied B reduced bursting of tubes, and addition of B to the culture media significantly increased pollen germination and pollen tube growth.


Blood ◽  
1992 ◽  
Vol 80 (3) ◽  
pp. 795-800 ◽  
Author(s):  
WE Sanders ◽  
RW Wilson ◽  
CM Ballantyne ◽  
AL Beaudet

Abstract P-selectin (CD62) is a rapidly inducible cell surface adhesion molecule that is expressed on platelets and endothelial cells and mediates their interaction with leukocytes. In vitro studies have suggested that this receptor may play an important role in hemostasis and in inflammatory response to tissue injury. We report the molecular cloning and sequencing of murine cDNA for P-selectin. The lectin, epidermal growth factor (EGF)-like, transmembrane, and cytoplasmic domains are highly conserved between mouse and human, with an overall amino acid identity of 79%. To further investigate the biology of this adhesion molecule in vivo, we analyzed mRNA levels for P-selectin in mice after injection with endotoxin. Northern blot data indicate that the cellular response in vivo includes a rapid increase in the level of mRNA, presumably for new synthesis of P-selectin. The increase in mRNA is maximal at 4 hours, and turnover is relatively rapid, with levels of RNA having decreased substantially by 6 hours following stimulation with endotoxin. After administration of endotoxin, the highest levels of mRNA expression were detected in liver, lung, kidney, and heart.


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