Impact of photoperiod on circadian trehalose and trehalase rhythms in the digestive system of silkworm, Bombyx mori

Circadian trehalose and trehalase rhythms were studied in the digestive system of Bombyx mori under 12 hr light-dark cycle (LD), continuous light (LL) and continuous dark (DD). The rhythmic changes were interpreted as synthetic cycles in gut wall and release cycles in gut lumen. The trehalose rhythm of gut wall comprised 8 trehalose synthetic cycles (TS cycles) under LD and LL and 7 under DD. The 24 hr trehalose rhythm of LD and LL was clock shifted to 27.2 hr under DD. The trehalose rhythm included 4 TR cycles under LD, 5 under LL and DD in the gut lumen and the 24 hr rhythm of LD was clock shifted to 19.2 hr under LL and DD. In the gut wall trehalase rhythm maintained 8 trehalase enzyme synthetic cycles (TES cycles) under LD, 10 LL and 7 under DD and the 24 hr rhythm of LD was clock shifted to 19.2 hr under LL and 27.2 hr under DD. In the gut lumen it included 4 TER cycles under LD and DD, 5 under LL and its 24-hr rhythm was advanced to 19.2 hr. Further analysis of data showed that LD favours trehalose synthesis, while LL and DD favour trehalase synthesis.

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Impact of photoperiod on circadian sucrose and sucrase rhythms in the digestive system of silkworm, Bombyx mori.

Journal of Applied and Natural Science ◽

10.31018/jans.v5i1.312 ◽

2013 ◽

Vol 5 (1) ◽

pp. 230-241

Author(s):

E. Bhuvaneswari ◽

B. Sailaja ◽

S. Sivaprasad

Keyword(s):

Bombyx Mori ◽

Digestive System ◽

Continuous Light ◽

Sucrose Uptake ◽

Gut Content ◽

Dark Cycle ◽

The Impact ◽

Silkworm Bombyx Mori

The impact of photoperiod on circadian sucrose and sucrase rhythms were analyzed in the digestive system of Bombyx mori under 12 hr light-dark cycle (LD), continuous light (LL) and continuous dark (DD). The rhythmic changes were interpreted as synthetic cycles in gut wall and release or uptake cycles in gut lumen. The gut wall comprised 6 sucrose synthetic cycles (SS cycles) under LD, LL and 5 under DD. The 24 hr rhythm of LD and LL was clock shifted to 28.8 hr under DD. In gut content, the sucrose rhythm showed 7 sucrose uptake cycles (SUcycles) under LD, 6 under LL and 5 under DD and the 24 hr rhythm of LD was clock shifted to 28.0 hr under LL and 34 hr under DD. In the gut wall sucrase rhythm maintained 7 SES cycles under LD and DD and 9 cycles under LL and its 24-hr rhythm is advanced to 18.2 hr. In the gut lumen 5 SER cycles under LD, 8 under LL and 6 under DD and its rhythm is advanced to 15 hr under LL and 20 hr under DD. Further analysis of data showed that LD favoured both synthesis and uptake of sucrose while LL, favoured the sucrase synthesis and its release.

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Photoperiod-induced clock-shifting in the circadian protein and amino acid rhythms in the larval fat body of silkworm, Bombyx mori

Journal of Applied and Natural Science ◽

10.31018/jans.v3i1.151 ◽

2011 ◽

Vol 3 (1) ◽

pp. 38-50

Author(s):

B. Sailaja ◽

S. Sivaprasad

Keyword(s):

Amino Acid ◽

Bombyx Mori ◽

Fat Body ◽

Continuous Light ◽

Fourth Instar ◽

Dark Cycle ◽

Response Curves ◽

Running Time ◽

Free Running ◽

Silkworm Bombyx Mori

The photoperiod-induced clock-shifting in the free running time of the circadian protein and amino acid rhythms was studied in the larval fat body of Bombyx mori. The analysis of peaks and troughs of phase response curves of the rhythm revealed that the fourth and fifth instar larvae grown under normal 12 h light and 12 h dark cycle (LD) showed 7 protein synthetic cycles, while those reared under continuous light (LL) recorded 9.5 cycles in fourth instar and 8 in fifth instar. Under continuous dark (DD), the protein rhythm maintained 8 cycles in fourth instar and 7.5 cycles in fifth instar. Clearly, both LL and DD conditions advance the 24-h free running time of the protein rhythm by durations ranging from 1.6 to 6.5 h. Comparative analysis of protein and amino acid rhythms shows that the photoperiod modulates the free running time of the former by altering the rate of amino acid mobilization.

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Photoperiodic modulation of circadian rhythms in the silk gland protein profiles of Bombyx mori and its influence on the silk productivity and quality

Journal of Applied and Natural Science ◽

10.31018/jans.v2i1.94 ◽

2010 ◽

Vol 2 (1) ◽

pp. 48-56 ◽

Cited By ~ 1

Author(s):

B. Sailaja ◽

S. Sivaprasad

Keyword(s):

Circadian Rhythms ◽

Bombyx Mori ◽

Continuous Light ◽

Silk Gland ◽

Protein Profiles ◽

Dark Cycle ◽

Response Curves ◽

Silk Proteins ◽

Free Running ◽

Clock Shift

Circadian rhythms in the silk gland protein profiles of Bombyx mori were analyzed under 12 h light and 12 h dark cycle (LD), continuous light (LL) and continuous dark (DD) conditions. The phase response curves of protein rhythms indicate the prevalence of a series of silk cycles, each comprising three phases; transcription, translation and consolidation of silk proteins. In the 24h- protein rhythm, the silk cycle repeats every 3h, 42 m under LD, 2h, 36m under LL and 3h under DD. The light and dark conditions advanced the rhythm of each silk cycle by 48m and 24m respectively. As a result the silk gland completes 7 rounds of protein synthesis under LD, 9 rounds under LL and 8 rounds under DD during the 24h-free running time of the rhythm. The light-induced clock-shift in the protein rhythm caused significant gains in economic parameters of sericulture with positive signals for enhancing silk productivity and quality.

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Photoperiod-modulated instar-specific clock-shifting in the circadian protein and amino acid rhythms in the larval segmental muscle of Bombyx mori

Journal of Applied and Natural Science ◽

10.31018/jans.v3i2.177 ◽

2011 ◽

Vol 3 (2) ◽

pp. 176-188

Author(s):

S. Sivaprasad ◽

B. Sailaja

Keyword(s):

Comparative Analysis ◽

Amino Acid ◽

Bombyx Mori ◽

Muscle Tissue ◽

Continuous Light ◽

Fourth Instar ◽

Dark Cycle ◽

Response Curves ◽

Amino Acid Profiles ◽

Free Running

The photoperiod-modulated clock-shifting in the circadian protein rhythm was studied in the segmental muscle of Bombyx mori. The analysis of phase response curves of the fourth instar rhythm revealed that the muscle tissue completes six protein synthetic cycles (PS cycles) under normal 12 hr light and 12 hr dark cycle (LD), 8 cycles each under continuous light (LL) and continuous dark (DD) conditions. The fifth instar protein rhythm showed seven PS cycles each under LD and DD conditions, but only six under LL. The protein rhythm gets clock-shifted in instarspecific and photoperiod-specific fashions. In the fourth instar, both LL and DD conditions advanced the 24 hr free running time of the rhythm by six hours and set it at 18 hr, but in the fifth instar it is delayed by 4 hr and set at ~28 hr under LL, but remained unchanged under DD. Comparative analysis of protein and amino acid profiles shows that the photoperiod modulates the protein rhythm by altering the rate of amino acid mobilization.

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