Diapause in Drosophila melanogaster females: a genetic analysis

Abstract

Female Drosophila melanogaster exhibit ovarian diapause at low temperatures and short day lengths. We found that D. melanogaster isofemale lines from Windsor (Ontario, Canada) had a significantly higher percentage of females in diapause than did those from Cartersville (Georgia, U.S.A.). To investigate the heredity of this trait, we performed a 16-reciprocal cross analysis using two extreme isofemale lines called W and C. We found that diapause in D. melanogaster is inherited as a simple autosomal recessive trait with the C response (less flies in diapause) completely dominant to the W one. Maternal and cytoplasmic factors did not affect differences in diapause in these lines. The result of our genetic analysis of diapause in D. melanogaster opens many avenues for the genetic dissection of this ecologically relevant trait.

Genetic Variance for Diapause Expression and Associated Life Histories in Drosophila Melanogaster

“…Studies by Richard et al (1998Richard et al ( , 2001) also implicated a role for ecdysteroids in mediating vitello- genesis and the diapause response and further supported that D. melanogaster diapause is under neuroendocrine control. The expression of diapause was shown to vary both among laboratory strains and natural populations (Williams and Sokolowski 1993). stated that the characteristics of ovarian diapause in D. melanogaster indicate that the trait is of relatively recent evolutionary origin; consistent with this hypothesis, diapause expression has not been observed in either East or West African D. melanogaster strains or in D. simulans (P. Schmidt, unpubl.…”

“…As in endemic temperate drosophilids (e.g., Lumme and Lakovaara 1983;Kimura 1988), D. melanogaster exposed to reduced temperatures (Ͻ14ЊC) and short photoperiods (Ͻ12 h light) can undergo a form of reproductive quiescence or diapause in which oogenesis is arrested in previtellogenic stages (Saunders et al 1989;Williams and Sokolowski 1993). Diapause expression in D. melanogaster and other Drosophila results in life-span extension, elevated resistance to multiple forms of environmental stress, and reduced rates of age-specific mortality Tatar 2004).…”

Natural variation in Drosophila melanogaster diapause due to the insulin-regulated PI3-kinase

“…Flies were grown under standard conditions at 25 Ϯ 0.5°C on a 12-h light͞12-h dark (12L:12D) light cycle as described in (10). Male and female flies were collected Ͻ8 h after eclosion and placed at 11 Ϯ 0.5°C under SD conditions (10L:14D).…”

“…The Windsor (W) natural variant from Canada exhibits an autosomal-recessive high-diapause phenotype compared with the Cartersville (C) natural variant from the Southern U.S., which confers a fully dominant low-diapause phenotype (10). Crosses between the variants suggested that diapause may be influenced by relatively few genes (10).…”

“…We used two natural diapause variants of D. melanogaster as a basis to identify genetic regulators of diapause (10). The Windsor (W) natural variant from Canada exhibits an autosomal-recessive high-diapause phenotype compared with the Cartersville (C) natural variant from the Southern U.S., which confers a fully dominant low-diapause phenotype (10).…”