Biomedical subjects

Jason Wood

Publications and source records attributed to Jason Wood.

3 recordsLinked to original sources

PubMed2004

Role of the N-terminal region of Rap1p in the transcriptional activation of glycolytic genes in Saccharomyces cerevisiae.

In the yeast two-hybrid system, the N-terminal region of Rap1p was shown to interact with Gcr1p and Gcr2p. Disruption of gcr1 and/or gcr2 in the two-hybrid reporter strain demonstrated that the interaction with Gcr1p does not require Gcr2p, whereas the interaction with Gcr2p is mediated through Gcr1p. Deletion of the N-terminal region of Rap1p alone did not show a growth phenotype, but a growth defect was observed when this mutation was combined with a gcr2 deletion. The poor growth of the gcr1 null mutant was not affected further by the N-terminal deletion of Rap1p, but the growth of gcr1 strains with mutations in the DNA binding region of Gcr1p was affected by the removal of the N-terminal region of Rap1p. These results suggest that one function of the N-terminal region of Rap1p, presumably the BRCT domain, is to facilitate the binding of Gcr1p to the promoter by a protein-protein interaction.

Blotting, Western↗

PubMed2002

Two different E2F6 proteins generated by alternative splicing and internal translation initiation.

E2F transcription factors play an important role in the regulation of cell cycle progression. E2F6, the most recently identified member of the E2F family, is a retinoblastoma-protein-independent transcriptional repressor that is required for developmental patterning of the axial skeleton. It has recently been shown that the E2f6 locus produces two different mRNAs, E2F6 and E2F6b. The E2F6b mRNA contains an additional exon that is inserted by alternative splicing. This exon contains an in-frame stop-codon and an in-frame translation initiation codon. However, whether a protein is translated from the E2F6b mRNA has not yet been addressed. We now show that internal translation initiation gives rise to E2F6b, an amino-terminal truncated E2F6 protein. We also show that E2F6 and E2F6b mRNAs are ubiquitously expressed in primary mouse tissues. During the cell cycle, the highest expression of both forms is found at the G1 to S transition. The 5' untranslated regions of E2F6 and E2F6b are unusually long, and they contain several upstream AUG codons followed by short reading frames. Our results suggest that translation of E2F6b is initiated by internal ribosome entry. We propose that regulated translation initiation can produce distinct E2F6 isoforms under different physiological conditions.

5' Untranslated Regions↗

PubMedDate not supplied

Transforming growth factor-beta levels during second- intention healing are related to the different course of wound contraction in horses and ponies.

Wound healing in horses is often complicated by wound infection, exuberant granulation tissue, and hypertrophic scars, especially when wounds are located on the limbs. Wound healing in ponies is less problematic, characterized by a greater degree of wound contraction and a more intense initial inflammatory response. Because both processes are influenced by transforming growth factor-beta (TGF-beta), it was hypothesized that the better wound healing in ponies was associated with different TGF-beta profiles. A series of small wounds was created on the distal limbs and hindquarters of ponies and horses. Tissue samples were harvested on alternate days until day 13 postwounding, and levels of total and active TGF-beta were determined. Levels of TGF-beta were significantly higher in pony wounds than in those of horses. The TGF-beta profile differed between limb and body wounds, with levels in body wounds decreasing at the end of the experiment and persisting in limb wounds. In ponies, the higher TGF-beta levels can, to a large extent, explain the more intense inflammatory response and may explain the greater degree of wound contraction. Apparently adequate levels in the limbs fail to result in greater wound contraction, probably because of a stronger fixation of the skin. The persistence of elevated levels of TGF-beta may result in the production of exuberant granulation tissue. Further research on the temporal patterns of the different TGF-beta isoforms seems indicated, because manipulation of TGF-beta levels appears to be a promising option for intervention in problematic wound healing in horses.

Actins↗