29.6 Posterior development uses another localized regulator Order of posterior pathway mutants Loca licatio n of p roduc ts in th e egg capuccio Common pathway Figure 29.8 The s妇uer, Staufen protein posterior pathway sk ar oskar has two branches mRNA responsible for vas a protein/ abdominal 记s development and tuor germ cell formation Polar granu es Urk nown de ter min ants A bdominal br anch G em ce ll bra nch na nos anos P ole ce lIs o mR NA fo rm pumic nanos protel 消当
Figure 29.8 The posterior pathway has two branches, responsible for abdominal development and germ cell formation. 29.6 Posterior development uses another localized regulator
has two nucl 29.6 Posterior development uses another localized Divisions 1-8(90 min Nuclei divide in common cytoplasm (syncytium). Nuclei in pol ar plasm(pink) regulator become gem cell precursors Figure 29. 2 The early Syncytial blastoderm(150 min) development of the Nuclei migrate to pen phery and divide: 4 further divisions occur (in close but not perfect synchrony Drosophila egg occurs in a common cytoplasm until the stage of cellular blastoderm ●●●●●●●●●●●● ellular blastoderm (195 mi 「 monolayer of-600 somatic c今 Membranes surround nuclei to for 消当
Figure 29.2 The early development of the Drosophila egg occurs in a common cytoplasm until the stage of cellular blastoderm. 29.6 Posterior development uses another localized regulator
29.6 Posterior development uses another localized regulator Donor VVild-type embrO Figure 29.6 Mutant embryos that cannot develop can be rescued by injecting cytoplasm taken from a wild-type embryo. The donor can be tested for time of appearance and location of the rescuing Remove material from donor activity; the recipient can be and microinject into recipient tested for time at which it is susceptible to rescue and the effects of injecting material at Recipient different locations Mutant embryo 消当
Figure 29.6 Mutant embryos that cannot develop can be rescued by injecting cytoplasm taken from a wild-type embryo. The donor can be tested for time of appearance and location of the rescuing activity; the recipient can be tested for time at which it is susceptible to rescue and the effects of injecting material at different locations. 29.6 Posterior development uses another localized regulator
29.6 Posterior nanos RNA is localized at the posterior end t the 3rd division development uses another localized regulator Figure 29.9 nanos products are localized at the posterior end of a Drosophila embryo. The upper photograph shows the tightly localized rna inthe very early nanos protein spre ads from the posterior end at the 8th division embryo (at the time of the 3rd nuclear division The lower photograph shows the spreadingof nanos protein at the 8th nuclear division. Photographs kindly provided by ruth lehmann 消当
Figure 29.9 nanos products are localized at the posterior end of a Drosophila embryo. The upper photograph shows the tightly localized RNA inthe very early embryo (at the time of the 3rd nuclear division). The lower photograph shows the spreadingof nanos protein at the 8th nuclear division. Photographs kindly provided by Ruth Lehmann. 29.6 Posterior development uses another localized regulator
29.7 How are mRNAs and Nursecells Ooc vte proteins transported and localized? Figure 29.10 Some mRNAs are RNA transported into the drosophila egg as ribonucleoprotein particles. They move to their Ribonucleoprotein final sites of localization by association with tracks that may bicoid mRNA loc aizes at anterior end Oskar mRNA moves down tracks to posterior end be either either microtubules or actin filaments bicoid oskar mRN六 一R六 消当
Figure 29.10 Some mRNAs are transported into the Drosophila egg as ribonucleoprotein particles. They move to their final sites of localization by association with tracks that may be either either microtubules or actin filaments. 29.7 How are mRNAs and proteins transported and localized?