The leaves of green plants as well as a cyanobacterium, a red alga, and fungi contain insulin-like antigens.
We report the detection of insulin-like antigens in a large range of species utilizing a modified ELISA plate assay and Western blotting. We tested the leaves or aerial parts of species of Rhodophyta (red alga), Bryophyta (mosses), Psilophyta (whisk ferns), Lycopodophyta (club mosses), Sphenopsida (horsetails), gymnosperms, and angiosperms, including monocots and dicots. We also studied species of fungi and a cyanobacterium, Spirulina maxima. The wide distribution of insulin-like antigens, which in some cases present the same electrophoretic mobility as bovine insulin, together with results recently published by us on the amino acid sequence of an insulin isolated from the seed coat of jack bean (Canavalia ensiformis) and from the developing fruits of cowpea (Vigna unguiculata), suggests that pathways depending on this hormone have been conserved through evolution.
Silva
L B
LB
Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ, Brasil.
Santos
S S S
SS
Azevedo
C R
CR
Cruz
M A L
MA
Venâncio
T M
TM
Cavalcante
C P
CP
Uchôa
A F
AF
Astolfi Filho
S
S
Oliveira
A E A
AE
Fernandes
K V S
KV
Xavier-Filho
J
J
D000818:Animals; D001426:Bacterial Proteins / Q000032:analysis / Q000235:genetics; D015153:Blotting, Western; D002417:Cattle; D000458:Cyanobacteria / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005658:Fungi / Q000737:chemistry* / Q000235:genetics; D007328:Insulin / Q000032:analysis*; D008970:Molecular Weight; D010940:Plant Proteins / Q000032:analysis* / Q000235:genetics; D011506:Proteins / Q000032:analysis*; D000461:Rhodophyta / Q000737:chemistry* / Q000235:genetics
D001426:Bacterial Proteins; D007328:Insulin; D010940:Plant Proteins; D011506:Proteins