As an initial step in the study of the molecular events surrounding the establishment of a mature root apex, analyses of the early germinative growth of the Allium radicle were undertaken. Changes in the level and pattern of the soluble proteins were investigated by polyacrylamide gel disc electrophoresis and Joyce‐Loebl densitometry. Histochemical studies revealed the presence of protein bodies in the terminal mm of the Allium radicle. These bodies underwent depletion and breakdown during germination. The results of the electrophoretic fractionation of the soluble proteins during germination showed that there was not a proliferation of protein components but, rather, a considerable change in the concentration of existing protein fractions. Several fractions, assumed to be components of the reserve or storage proteins, showed a quantitative depletion correlated in time with the loss of the protein bodies. Quantification of the soluble proteins during germination showed a 32% decrease per radicle tip over a 67‐hour period, but when expressed on a per cell basis a 32% increase was noted. A dramatic increase in protein synthesis, as measured by 3H‐leucine incorporation, was initiated after 36 hours' exposure to germinative conditions, that is, at the beginning of radicle protrusion. A time‐ordered sequence of events was noted for the depletion of the protein bodies and their assumed reserve components, suggesting their ultimate utilization in new protein synthesis.
|Original language||English (US)|
|Number of pages||8|
|State||Published - Jan 1 1971|
ASJC Scopus subject areas
- Plant Science
- Cell Biology