Dataset Information

Expression of the phycobiliprotein antenna of the cryptophyte alga Guillardia theta

ABSTRACT: Plants and algae have developed various light harvesting mechanisms for optimal delivery of excitation energy to the photosystems. The cryptophyte algae have evolved a novel soluble light-harvesting antenna utilizing phycobilin pigments to complement the membrane-intrinsic Chl a/c-binding LHC antenna. This new antenna consists of the plastid-encoded beta-subunit, a relict of the ancestral phycobilisome, and a novel nuclear-encoded -subunit unique to cryptophytes. Together, these proteins form the active tetramer, which consists of one alpha 1 and one alpha 2 and two beta susbunits. In all cryptophyte algae investigated so far, the alpha-subunits have duplicated and diversified into a large gene family. Although there is transcriptional evidence for expression of all these genes, the x-ray structures determined to date suggest that only two of the -subunit genes might be significantly expressed at protein level. Using proteomics, we show that phycoerythrin 545 (PE545) of Guillardia theta, the only cryptophyte with a sequenced genome, all 20 alpha-subunits are expressed when the algae grow under white light. Their relative expression levels depend on the intensity of the growth light, but there is no evidence for a specific light-dependent regulation of individual members of the alpha-subunit family under the growth conditions applied. Subunit GtcpeA10 seems to be a special member of the alpha-subunit family, because it consists of two similar N- and C-terminal domains, which likely are the result of a partial gene duplication.

INSTRUMENT(S): Synapt MS

ORGANISM(S): Guillardia Theta Ccmp2712

TISSUE(S): Photosynthetic Cell, Cell Culture

DISEASE(S): Disease Free

SUBMITTER: Thomas Kieselbach

LAB HEAD: Thomas Kieselbach

PROVIDER: PXD006301 | Pride | 2017-06-20

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	2016_11_22_G_theta_HL1_S1_to_S3.raw.zip	Raw
	2016_11_22_G_theta_HL2_S1_to_S3.raw.zip	Raw
	2016_11_22_G_theta_HL3_S1_to_S3.raw.zip	Raw
	2016_11_22_G_theta_HL4_S1_to_S3.raw.zip	Raw
	2016_11_22_G_theta_HL5_S1_to_S3.raw.zip	Raw

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Publications

Proteomic analysis of the phycobiliprotein antenna of the cryptophyte alga Guillardia theta cultured under different light intensities.

Kieselbach Thomas T Cheregi Otilia O Green Beverley R BR Funk Christiane C

Photosynthesis research 20170524 1-3

Plants and algae have developed various light-harvesting mechanisms for optimal delivery of excitation energy to the photosystems. Cryptophyte algae have evolved a novel soluble light-harvesting antenna utilizing phycobilin pigments to complement the membrane-intrinsic Chl a/c-binding LHC antenna. This new antenna consists of the plastid-encoded β-subunit, a relic of the ancestral phycobilisome, and a novel nuclear-encoded α-subunit unique to cryptophytes. Together, these proteins form the activ ...[more]

PMID: 28540588

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