FLR-2, the glycoprotein hormone alpha subunit, is involved in the neural control of intestinal functions in Caenorhabditis elegans.
The intestine plays an essential role in organism-wide regulatory networks in both vertebrates and invertebrates. In Caenorhabditis elegans, class 1 flr genes (flr-1, flr-3 and flr-4) act in the intestine and control growth rates and defecation cycle periods, while class 2 flr genes (flr-2, flr-5, flr-6 and flr-7) are characterized by mutations that suppress the slow growth of class 1 flr mutants. This study revealed that flr-2 gene controls antibacterial defense and intestinal color, confirming that flr-2 regulates intestinal functions. flr-2 encoded the only glycoprotein hormone alpha subunit in C. elegans and was expressed in certain neurons. Furthermore, FLR-2 bound to another secretory protein GHI-1, which belongs to a family of lipid- and lipopolysaccharide-binding proteins. A ghi-1 deletion mutation partially suppressed the short defecation cycle periods of class 1 flr mutants, and this effect was enhanced by flr-2 mutations. Thus, FLR-2 acts as a signaling molecule for the neural control of intestinal functions, which is achieved in a functional network involving class 1 and class 2 flr genes as well as ghi-1. These results are informative to studies of glycoprotein hormone signaling in higher animals.
Oishi
Akane
A
Structural Biology Center, National Institute of Genetics, Mishima 411-8540, Japan.
Gengyo-Ando
Keiko
K
Mitani
Shohei
S
Mohri-Shiomi
Akiko
A
Kimura
Koutarou D
KD
Ishihara
Takeshi
T
Katsura
Isao
I
D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000382:microbiology / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000502:physiology; D015292:Glycoprotein Hormones, alpha Subunit / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D054884:Host-Pathogen Interactions; D007422:Intestines / Q000294:innervation* / Q000502:physiology*; D008017:Life Expectancy; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009154:Mutation; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D010858:Pigmentation; D011485:Protein Binding; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D018076:DNA, Complementary; C547099:GHI-1 protein, C elegans; D015292:Glycoprotein Hormones, alpha Subunit; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins