Drosophila larvae

Since 2002, on-line nanoscale LC-ESI-MS/MS was used for the analysis of the peptidome of. Drosophila samples. This combination greatly improves the sensitivity of detection. Starting from only 50 larval Drosophila CNS, 28 peptides were isolated and sequenced in an on-line quadrupole time-of-flight mass spectrometer [27]. Later, two-dimensional capillary LC-ESI-MS/MS has enhanced the coverage of this peptidomics analysis with the identification of twenty additional peptides [31]. The CNS extract has been first fractionated onto a strong cation-exchange column then onto a reversed-phase column before ESI-MS/MS analysis. Recently this approach has been applied to Drosophila larvae hemolymph to identify new peptides induced by a septic injury [22]. Most of the identified molecules correspond to truncated forms or propeptides of known AMPs and DIMs [15,20,21], but two previously unknown peptide precursors, potentially involved in the innate immune response, have been also detected by this way. 

Kreher SA et al (2005) The molecular basis of odor coding in the Drosophila larva. Neuron 46 445-456... 

Aceves-Pina EO, Quinn WG (1979) Learning in normal and mutant Drosophila larvae. Science 206 93-96... 

Scherer S, Stocker RF, Gerber B (2003) Olfactory learning in individually assayed Drosophila larvae. Learn Mem 10 217-225... 

Hooper, J. E. (1986). Homeotic gene function in the muscles of Drosophila larvae. EMBO J. 5 2321-2329. 

Steller, H. and V. Pirrottta. (1985) "A transposable P vector that confers selectable G418 resistance to Drosophila larvae." EMBO J. 4 167-171. 

To determine what cells make the immune-specific RNA we inoculated mid-third instar Drosophila larvae with bacteria and six hours later dissected them into fat bodies and fat body-free carcass. Total RNA was collected, separated by electrophoresis, transfered to nitrocellulose, and probed with labelled Pool 1 oligonucleotide. The results showed (Fig. 5) that intact inoculated larvae accumulate the immune-specific transcript while intact control larvae do not. The tissue dissection experiment showed that fat body cells of inoculated larvae contain transcripts homologous to the immune-specific probe, but the carcass does not. We conclude that fat body cells in Drosophila larvae accumulate a transcript that has homology to sarcotoxin when they have been inoculated with bacteria. We are currently cloning the responsible immune gene. 

Figure 5. Drosophila fat body cells accumulate immune-specific RNA. Drosophila larvae were inoculated with bacteria and six hours later RNA was extracted from either whole larvae, from fat body, or from the carcasses minus fat body. These RNAs were separated on the gel shown on the right stained with ethidium bromide, then northern blotted and probed with the oligonucleotide on the left.

Kunte AS, Matthews KA, Rawson RB. Fatty acid auxotrophy in Drosophila larvae lacking SREBP. Cell Metab 3(2006) 439M48. 

My own interest in nucleic acid base-analogues began during my investigation into the mechanism of mutagenesis induced by formaldehyde m Drosophila larvae. 

Formaldehyde administered by larval feeding therefore induces a wide variety of major genetic effects, which contrasts with the simple base pair changes largely found to be induced by nucleic acid base-analogues in prokaryotes. Several mutagenic purine and pyrimidine base-analogues of this latter type have been tested on Drosophila larvae, but found not to induce mutation [10] namely, 2-aminopurine 2,6-diaminopurine 5-bromodeoxyuridine and 5-bromodeoxycytidine. 

In conclusion therefore, it is possible that the A G and G"G dimers contribute to the cytotoxic effects produced by their utilisation in RNA synthesis, but that the major cytotoxic effect is due to the N-hydroxymethyl derivatives. If the dimers are producing an effect, then the N-hydroxymethyl derivatives may exhibit more specificity towards tumour cells than so far seems indicated. Later experiments with formaldehyde-treated RNA, under conditions where negligible dimer formation takes place [5], still show a strong cytotoxic effect (T. Alderson, unpubl. data), as is also the case for its mutagenic activity in Drosophila larvae [7]. This implicates the N-hydroxymethyl derivatives as the active products. 

Sobels FH (1954) Injection of formaldehyde into Drosophila larvae. Drosophila Inf Serv 28 156-157... 

Gilpin, M. E. (1974) Intraspecific competition between Drosophila larvae in serial transfer systems. Ecology, 55, 1154-9. 

In other experiments with Drosophila species, Fischer et al. (19) have shown that GAL4, when expressed in particular tissues of Drosophila larvae, stimulates tissue-specific transcription of a Drosophila promoter linked to... 

The coexistence of neutral and autofluorescent lipid species in living C. elegans was demonstrated by Le et al. [38], who also analyzed the unsaturation level of lipids in wild-type and mutant C, elegans by coupling CARS with fingerprint confocal Raman analyses. The lipid metabolism was also studied by CARS in living Drosophila larvae [39]. 

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