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CLOCK GENES. "In Arabidopsis and other plants, several genes with a circadian expression pattern have been identified, for example, a catalase, cysteine protease, a putative β‐amylase, nitrate reductase, sucrose phosphate synthase, and chlorophyll a/b binding proteins (Cab) of photosystems I and II." https://lnkd.in/eTEzGE9 View in LinkedIn

RHYTHM SLIPS. "When plants of Cereus grandifolius (a night‐bloomer) were kept in darkness during the day and exposed to light at night, the normal periodicity was retained for some days but gradually became weaker, and then assumed a new phase in which opening occurred at the end of the light period." https://lnkd.in/eTEzGE9 View in LinkedIn

RHYTHM FLIPS. "In light/dark (LD) cycles of 6 h or 9 h, flower opening followed the imposed cycle (i.e. they were 6 h open and 6 h closed, etc). Interestingly, if the light and dark periods were made as short as 2 h, the flowers again showed a 24 h rhythm. Within limits, therefore, the endogenous rhythm can become entrained by shorter light/dark cycling. Entrainment is defined as the process whereby the plant, exposed to repeated periods of light and darkness with a period P, changes its rhythm to the same period." https://lnkd.in/eTEzGE9 View in LinkedIn

DARK TRIGGER. "The time of the onset of darkness, however, had a large effect on the rhythm. In plants grown in the field and brought into 12 h darkness, starting at 12 noon, the flowers from then on showed a 24 rhythm whereby they followed the new cycle. Normally all flowers on a plant opened and closed at the same time. However, if buds on the same plant were placed in darkness at various times, they opened and closed at different times, set by the time of the onset of continuous darkness." https://lnkd.in/eTEzGE9 View in LinkedIn

EVOLUTIONARY PATHWAY. "RNA cultures with eukaryote-like RNA-processing seem to predate the evolution of prokaryotes, which adapted to fast-changing environmental conditions by reducing their genomic content to a DNA with nearly analog (intron-free) protein-coding data-sets. This could be the evolutionary pathway from ribozymes of the early RNA world to ribonucleoproteins via low complexity RNA-chaperones to a DNA-protein-based life." https://lnkd.in/ekWBG2q View in LinkedIn

ENDOGENOUS CLOCKS. "The 24 h rhythm in continuous darkness also occurred in plants that had previously been subjected to a day/night cycle of 6 h rather than 12 h, in plants that had been held under continuous light, and in plants previously subjected to irregular periods of light and darkness. The flowers thus show a rhythm based on a clock that apparently resides in the flower, and which is unaffected by the light/dark regime prior to continuous darkness." https://lnkd.in/eTEzGE9 View in LinkedIn

FOOTNOTE. "For many years, all bacteria were believed to have a single, circular chromosome in comparison to the eukaryotes, which have linear chromosomes. Perhaps, this was due to the limited sample of bacterial strains studied at the time and the sequencing techniques available to examine the bacterial chromosomes. However, this belief was disproved when bacteria with multiple and/or linear chromosomes were discovered in 1989." https://lnkd.in/eEQunTJ View in LinkedIn

LEAF VS FLOWER CLOCKS. "When grown outdoors, the flowers of C. arvensis open in the morning and close in the afternoon, for about 5 d prior to petal wilting. Temperature changes had no effect on opening or closure. Under continuous darkness, opening and closure showed a 24 h rhythm. When the leaves were subjected to a different day/night cycle from the flowers, the opening and closing rhythm followed that of the flowers." https://lnkd.in/eTEzGE9 View in LinkedIn

FASTER ADAPTATION. "In contrast, circular genomes with few higher order regulatory elements (represented by a diversity of genetic parasites present in intron-like genomic habitats) had more advantages in a high temperature environment and could adapt faster because of their ability to exchange selected phenotypes within and between protein-coding data-sets, as happens in horizontal gene transfer." Many bacterial genomes are circular. https://lnkd.in/ekWBG2q View in LinkedIn

DAY TETHERING. "Floral opening in several species is apparently independent of specific external regulation as it occurs at any time of the day. Floral opening in other species, belonging to a large number of families, show a relationship with the time of day. Flower closure may similarly be independent or dependent of the time of the day, depending on the species. This dependence on the time of the day may be regulated by external cues such as temperature, humidity, and light and/or by an internal rhythm." https://lnkd.in/eTEzGE9 View in LinkedIn