Cell size control by ovarian factors regulates juvenile hormone synthesis in corpora allata of the cockroach, Diploptera punctata.
The corpora allata synthesize and release juvenile hormone (JH) that in turn regulates insect growth, metamorphosis and reproduction. In the corpus allatum (CA) of the female adult cockroach Diploptera punctata, cyclic rise and decline in JH synthesis rates occur concurrently with cyclic growth and atrophy during an ovarian cycle. Here, we report that protein content decreases, whereas Golgi population, lysosomal content and autophagic activities increase with decrease in CA cell size. Also, the concentration of cyclic GMP (cGMP) is low in large cells and high in small cells. Results of treating CA with ovarian tissue suggest that a putative peptidergic growth regulator released from mature ovaries acts directly on active CA cells and induces the elevation of intracellular cGMP content. Consequently, elevated cGMP may inhibit protein synthesis or trigger massive and synchronous autophagic activities, resulting in cell atrophy and reduction of protein content. As a result of the depletion of cellular machinery, CA glands exhibit long-term depression in JH synthesis.
Chang
Ling-Wen
LW
Department of Life Science, Institute of Biotechnology, National Tsing Hua University, 101, Section 2 Kuang Fu Road, Hsinchu 30043, Taiwan.
Tsai
Chuan-Mei
CM
Yang
De-Ming
DM
Chiang
Ann-Shyn
AS
D000818:Animals; D048429:Cell Size; D003058:Cockroaches / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D003335:Corpora Allata / Q000166:cytology / Q000378:metabolism*; D006152:Cyclic GMP / Q000378:metabolism / Q000502:physiology; D005260:Female; D007301:Insect Hormones / Q000502:physiology*; D007605:Juvenile Hormones / Q000096:biosynthesis*; D010053:Ovary / Q000502:physiology
D007301:Insect Hormones; D007605:Juvenile Hormones; D006152:Cyclic GMP