How can you relate the movement of the canoe to one of the cell modicfications in its environment
Answers
Answer:
Explanation:
Just when it seemed that Canoe was being understood in terms of its interaction with the Notch pathway, it was also becoming clear that Canoe and its mammalian homolog AF-6 physically interact with Ras (Kuriyama, 1996). Morphological studies of the fly's compound eye suggest that induction of photoreceptors, including the R7 photoreceptor, is unaffected by cno mutations. The linear alignment of the R7 photoreceptor is disrupted in the pupal retina of cno mutants, but without exception a single R7 photoreceptor is formed in each ommatidium in cno mutant retinae (Matsuo, 1997). Since Ras signaling is involved in R7 fate determination (see Sevenless), what exactly is the role of Canoe in eye development?
It has been suggested that R7 photoreceptors occupy unusual positions in pupal discs because the mutant discs fail to form a correct mesh of pigment cells, which shape ommatidia into regular hexagonal structures. A strong mutation in cno eliminates from one to three cone cells from most ommatidia. In contrast, overexpression of cno+ results in the formation of supernumerary cone cells. These results indicate that an increase in cno+ expression promotes cone cell induction and a significant decrease in cno+ expression prevents cone cell precursors from differentiating into cone cells (Matsuo, 1997).