Regulation of Prox 1 during lens regeneration.
OBJECTIVE
To determine the expression pattern of Prox 1 during the process of lens regeneration in the urodele Notophthalmus viridescens.


METHODS
Polymerase chain reaction was performed to amplify a partial newt Prox 1 sequence. In situ hybridization and immunodetection methods were used to detect the Prox 1 mRNA and the Prox 1 protein, respectively.


RESULTS
Prox 1 mRNA was present in the retina and in the lens (in the epithelium and bow region) of the intact eye. Prox 1 protein was found to be predominantly present in the lens and dorsal iris of the intact eye, although some trace levels of Prox 1 protein were detected in the ventral iris as well. After lentectomy, expression of the mRNA was also pronounced in the dorsal dedifferentiating iris and the regenerating lens. The ventral iris also expressed Prox 1 but seemingly at lower levels. Although Prox 1 protein showed upregulation in the dorsal iris during the process of lens regeneration, trace levels were also detected in the ventral iris. In the retina, Prox 1 protein was distributed in horizontal cells of the inner nuclear layer, whereas the mRNA was expressed in all layers of the retina.


CONCLUSIONS
Prox 1 was unevenly distributed in the intact cells of the newt iris, with significantly higher levels of Prox 1 protein present in the dorsal versus the ventral margin. This protein was differentially regulated during the process of lens regeneration, with obvious upregulation in the dorsal iris. Prox 1 is the first transcriptional factor to be shown to be regulated in the dorsal versus ventral iris during the process of lens regeneration.
Del Rio-Tsonis
K
K
Department of Biology, University of Dayton, Ohio 45469-2320, USA.
Tomarev
S I
SI
Tsonis
P A
PA
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D017931:DNA Primers / Q000737:chemistry; D015342:DNA Probes / Q000737:chemistry; D019084:Fluorescent Antibody Technique, Indirect; D015870:Gene Expression; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D017403:In Situ Hybridization; D007498:Iris / Q000378:metabolism; D007908:Lens, Crystalline / Q000502:physiology*; D008969:Molecular Sequence Data; D009673:Notophthalmus viridescens; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D012038:Regeneration / Q000502:physiology*; D012160:Retina / Q000378:metabolism; D025521:Tumor Suppressor Proteins; D015854:Up-Regulation; D000098551:Prospero-Related Homeobox 1 Protein
D017931:DNA Primers; D015342:DNA Probes; D018398:Homeodomain Proteins; D012333:RNA, Messenger; D025521:Tumor Suppressor Proteins; D000098551:Prospero-Related Homeobox 1 Protein