Germline Clone Analysis for Maternally Acting Drosophila Hedgehog Components

Abstract We have conducted a genetic and developmental analysis of the 26 contiguous genetic complementation groups within the 19D3-20F2 interval of the base of the X chromosome, a region of 34 polytene bands delimited by the maroon-like and suppressor of forked loci. Within this region there are four loci which cause visible phenotypes but which have little or no effect on zygotic viability (maroon-like, little fly, small optic lobes and sluggish). There are 22 loci which, when mutated, are zygotic lethals and three of these, legless/runt, folded gastrulation and 13E3, have severe effects on embryonic development. In addition, three visible phenotypes have been defined only by overlapping deficiencies (melanized-like, tumorous head, and varied outspread). We have analyzed the lethal phases and maternal requirement of 58 mutations at 22 of the zygotic lethal loci by means of germline clone analysis using the dominant female sterile technique. Additionally, all lethal complementation groups, as well as a specific subset of deficiencies, have been studied histologically for defects in the development of the central and peripheral embryonic nervous systems.

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Temporal variation in maximum cell-specific nitrification rate

Water Science & Technology ◽

10.2166/wst.2010.978 ◽

2010 ◽

Vol 61 (8) ◽

pp. 2069-2073 ◽

Cited By ~ 6

Author(s):

M. Fujita ◽

K. Tsuji ◽

A. Akashi

Keyword(s):

Ammonia Oxidation ◽

Thermal Power ◽

Nitrification Rate ◽

Nitrite Oxidation ◽

Cell Numbers ◽

Oxidation Rates ◽

Batch Tests ◽

Nitrogen Loads ◽

Clone Analysis ◽

Maximum Cell

The cell numbers of ammonia-oxidising bacteria (AOBs), Nitrospira and Nitrobacter in activated sludge used to treat wastewater from a thermal power plant in Japan were examined for nine months using a real-time PCR quantification technique. AOB cell numbers ranged 2.8 × 1010–2.3 × 1011 cell/L. The amoA clone analysis showed that the only Nitrosomonas halophila was responsible for ammonia oxidation over the period. Nitrospira were in the range of 2.6 × 109–2.4 × 1010 cell/L and Nitrobacter were less than 1% as common as Nitrospira. Meanwhile, maximum nitrification rates, maximum ammonia- and nitrite-oxidation rates obtained from aerobic batch tests, ranged 0.5–1.3 mmol-N/L h and 1.0–2.5 mmol-N/L h, respectively. No clear correlations were observed between the cell numbers of AOBs or Nitrospira and their maximum rates, because the maximum cell-specific ammonia- and nitrite-oxidation rates varied remarkably over the ranges of 1.1–11.9 and 2.4–21.6 fmol-N/cell h, respectively. To explore the factors controlling maximum cell-specific nitrification rates, the relationship to influent nitrogen loads per AOB or Nitrospira cell numbers was investigated. Fairly good correlations were obtained. Considering the effluent ammonia and nitrite concentrations were zero and only Nitrosomonas halophila had a role in ammonia oxidation over the period, we conclude that the amount of nitrogen oxidised per AOB or Nitrospira cell numbers likely controls maximum cell-specific ammonia- or nitrite-oxidation rates, respectively.

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