Figure 5.

PG mRNA accumulates in the embryo and the endosperm cap. A, In situ analysis detected expression of LeXPG1 mRNA in tomato embryos in a distinct band behind the radicle tip where it first emerged from the surrounding endosperm. Some expression was also detected in the remaining pieces of the endosperm cap. B, Section of the same seed as in A but probed with the sense strand RNA. C, At later stages of radicle protrusion, expression of LeXPG1 occurred throughout the embryo, but was most prominent in the vascular trace around the point of egress from the endosperm. Expression remained high in the endosperm cap. D, Section of the same seed as in C but probed with the sense strand RNA. Message was not observed in situ prior to the completion of germination (data not shown). Bars = 1 mm.