Home • Zygnema circumcarinatum UTEX 1560
Zygnema circumcarinatum UTEX 1560 [Image credit: Xuehuan Feng]
Zygnema circumcarinatum UTEX 1560 [Image credit: Xuehuan Feng]
Zygnema circumcarinatum UTEX 1560 [Image credit: Xuehuan Feng]

The Zygnema circumcarinatum UTEX 1560 genome assembly and gene models have not been determined by the JGI, but were downloaded from the Feng et al., 2023 genome supplemental data share at https://bcb.unl.edu/Zygnema_4genomes/ (Yanbin Yin Lab, University of Nebraska - Lincoln) on January 24, 2023. Please note that this copy of the genome is not maintained by the Yin Lab and is therefore not automatically updated. In order to allow comparative analyses with other algal genomes sequenced by the JGI, a copy of this genome is incorporated into PhycoCosm. The JGI Annotation Pipeline was used to add functional annotation to this genome.

Zygnema circumcarinatum UTEX 1560

The class of Zygnematophyceae has been pinpointed as the algal sister lineage to land plants. This class is named for filamentous algae of the genus Zygnema, which are known to occur in challenging environments and are desiccation resistant. Four strains (SAG 698-1a, SAG 698-1b, UTEX 1559, UTEX 1560) were sequenced, capturing the strain history of the + and - mating types derived from the Zygnema circumcarinatum sample of 1929 by Czurda. Of these, SAG 698-1a likely now represents a different species, Zygnema cf. cylindricum. Owing to their key phylogenetic position, genome data on these organisms shed light on the evolution of the genetic toolbox for multicellular growth and response to environmental challenges.

The filamentous green alga Zygnema circumcarinatum UTEX 1560 is a member of family Zygnemataceae, order Zygnematales, and class Zygnematophyceae. UTEX 1560 was isolated by Gauch as a spontaneous mutant of IUCC 43 with an increased cell size and chloroplasts numbers (Gauch, 1966). IUCC 43 was originally isolated by V. Czurda and maintained at the University of Texas at Austin’s Culture Collection of algae. Both UTEX 1560 and IUCC 43 were able to conjugate with the functional mating (+) strain of Z. circumcarinatum (Gauch, 1966), which is currently missing in any public algal culture collections. UTEX 1560 has a cell width of 22~24 µm that is similar to that of SAG 698-1b and UTEX 1559. UTEX 1560 and SAG 698-1b share identical plastomes and mitogenomes. UTEX 1560 has unbranched filaments and each cell contains a single nucleus located between the two star-shaped chloroplasts.


Gauch HG. (1966) Studies on the life cycle and genetics of Zygnema. [Master’s Thesis]. Ithaca, NY: Cornell University.

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