While chico1/chicoKG00032 females produce similar amount of eggs as controls, ovaries show decreased mtDNA replication in region 2B and 3 cysts, and eggs show severely decreased levels of mtDNA.
chico1 mutant flies show decreased learning index in a behavioral olfactory learning assay (measuring 3 min memory) compared to controls.
chico1 homozygotes display decreased number of Kenyon cell in the brain compared to controls.
chico1 mutant salivary gland cells exhibit wild-type endoplasmic reticulum and Golgi organisation.
chico1/+ mutants do not exhibit any significant difference in the number of dopaminergic neurons in newly eclosed adult males, and these flies do not display any significant reduction in climbing ability.
Homozygous and chico1/chicoflp147E adults show normal odour and electric shock reactivity.
Homozygous and chico1/chicoflp147E adults show significant impairment in 3 minute, 1 hour and 3 hour memory after olfactory aversive conditioning. Analysis using a short-duration training protocol indicates that the defect appears to be in the initial learning, since after normalising 3 minute memory in chico1 and wild-type flies, subsequent memory decay is indistinguishable in the two genotypes.
The brains of homozygous flies are significantly smaller than normal, with a significant reduction in the number of Kenyon cells and in the size of the mushroom bodies.
Mutant flies have a significantly reduced body size compared to controls. Wing cell size is reduced compared to controls.
Heterozygous females show an extension of median lifespan compared to wild-type controls. These females show accelerated accumulation of cytosolic hydrogen peroxide in the gut compared to wild-type controls.
Heterozygous males do not show an extension of median lifespan compared to wild-type controls. These males show a delayed accumulation of cytosolic hydrogen peroxide in the gut compared to wild-type controls.
Homozygous chico1 mutant adult flies have a reduced body weight compared to heterozygous controls. Wing area is also reduced compared to controls.
Lipid content is increased in homozygous chico1 mutant flies compared to controls. Carbohydrate content is similar to controls.
Homozygous chico1 mutant flies exhibit defective electroretinogram (ERG) readings.
Cholinesterase activity is significantly reduced in homozygous chico1 mutant flies compared to controls.
The frequency of proliferating cells in the intestine of aging chico1 homozygotes is significantly lower than that of age-matched controls.
Heterozygous flies show increased resistance to dry starvation compared to control flies.
The length of the dorsal hemisegments along the antero-posterior axis in chico1 mutant larvae is only 10% of that of wild-types.
In a fed state, chico1 flies are anoxia tolerant (heterozygotes are not).
Heterozygous ovaries transplanted into homozygous females usually show a robust vitellogenic response, with vitellogenic oocytes spanning the entire range of stage 8 to mature stage 14 eggs being seen in the transplanted ovaries. In all cases, the oocytes of the homozygous host female terminate development at the previtellogenic stage 7.
Homozygous ovaries transplanted into heterozygous or wild-type females fail to develop oocytes beyond stage 7, even though the host ovaries become fully vitellogenic in each recipient female.
Methoprene does not stimulate vitellogenesis or egg production in homozygous females.
On day 1 post-eclosion, homozygous females contain an average of 11.2 nurse cells per egg chamber, and on day 4 they have an average of 14.8 nurse cells per egg chamber (a statistically significant difference).
chico1 mutants show a reduction in wing size compared to wild-type controls. However, this phenotype is not temperature sensitive as chico1 flies raised at 25oC show a similar decrease in wing area compared to chico1 flies raised at 18oC to the decrease in wing area observed for control flies at these two temperatures.
Males that carry chico1 Minute clones throughout one side of the genitals and are heterozygous for chico1 on the other side show smaller genital arches on the homozygous clone side than on the heterozygous side. The difference in size is 16%. Maxillary palps consisting of chico1 homozygous clones are 45% smaller than paired palps on the same male.
chico1 homozygous adults are abnormally small and have reduced numbers of ommatidia per eye.
chico1 homozygous mutants are small, weighing on average 44% of the mass of wild-types. Mean oxygen consumption is not significantly higher than in wild-type flies. Mass-specific resting heat production is the same in chico1 mutants as wild-type flies. Dietary-restriction of chico1 mutants has no effect on resting heat production. While the body mass of wild-type flies fed on an energy restricted medium is reduced, chico1 mutants show no decrease in body mass.
chico1 flies are small and live ~50% longer than wild-type flies. These flies have low rates of pacing-induced heart failure and arrest, and their heart beat frequency does not increase with age, compared to wild-type flies. chico1/+ flies have lifespans that are longer than wild-type flies, but shorter than chico1 homozygotes. Like wild-type flies, these chico1/+ flies experience stress-induced heart failure and their heart beat frequency decreases with age. There is no difference between male or female flies for any of the heart functions tested in homozygous or heterozygous chico1 flies.
chico1/chicoflp147E flies show lower body weight, fewer ommatidia, smaller wings, fewer cells per wing and smaller wing cell area than wild type.
Photoreceptor cell projection patterns are indistinguishable from wild type in homozygous larvae and in mosaic larvae in which homozygous clones have been induced in the eye. The pattern of R7 and R8 projections in the medulla is similar to wild type in mosaic adults in which homozygous clones have been induced in the eye. Heterozygotes have normal photoreceptor cell projections in the medulla.
The relation between life-span and food concentration is right-shifted in chico1 females compared to controls. Control and chico1 females show similar peak life-spans under dietary restriction, but chico1 females show a peak in mean lifespan at a food concentration 0.8 times that of normal, while control females show a peak in mean lifespan at a food concentration 0.65 times that of normal.
chico1 adults are resistant to starvation conditions compared to wild type.
Homozygous adults are dwarf in size. Homozygous females show an increase of median and maximum life-span of up to 48 and 41% respectively compared to controls. Homozygous males are slightly short-lived. Heterozygous females and males show an increase in median life-span of up to 36 and 13% respectively. Heterozygous females have reduced fecundity and homozygotes are almost sterile. Mutant flies show no resistance to heat stress at 37oC. Slight resistance to oxidative stress (methyl viologen) is seen in heterozygotes but not in homozygotes. Heterozygotes and homozygotes show some resistance to starvation.
The chico1 mutation partially impaired the ability of follicle cells to proliferate faster in the presence of abundant nutrients. Egg chambers do not develop beyond vitellogenic stages in homozygotes, even in the presence of abundant food.
chico1 flies do not show unexpanded wings, are not dark and do not show male sterility.
Homozygous clones are not visible in the adult eye because they are out-competed by heterozygous cells.
Homozygosity for chico1 causes semilethality and an overall delay in development. Flies eclose 2-3 days after their heterozygous siblings. In non-crowded culture conditions, homozygous mutant mothers can produce few viable progeny lacking both maternal and zygotic chico function. Homozygotes have a drastic weight reduction (65% in females, 55% in males) compared to wild-type. Body size reduction is observed at all developmental stages but does not alter the overall proportions of the flies. Homozygous clones in the eye produce morphologically normal ommatidia, except that they are more than 50% smaller than wild-type. Otherwise normal ommatidia with both smaller mutant and larger wild-type photoreceptors are observed at the edges of clones, indicating that chico acts cell autonomously. Autonomy of cell size control is also observed in mutant clones in the wing. Selective removal of chico1 function in the eye imaginal disc cells generates flies with a strongly reduced head capsule and reduced eyes, whereas the proboscis and the rest of the body are of wild type size. Homozygous mutant clones in the adult eye are rarer, more variable in size and on average smaller than their wild-type sister clones. Clones are more frequently observed in the anterior half of the eye around the equator. In the eye disc, clones are also more variable in size and on average smaller than their wild-type sister clones. TUNEL analysis shows no increase in apoptotic cells in homozygous clones. Clones produced in a Minute background do not reveal enhanced apoptosis compared to wild type clones, or any increase in morphological signs of programmed cell death, in either the imaginal discs or the adult eye. No significant difference is seen in the apoptotic sub-G1 fraction of homozygous mutant cells compared to heterozygous cells.
Mutant flies develop slower than sibling controls and have a reduced body size. chico mutant cells differentiate normally but are significantly reduced in size.
male fertility poor female-sterile