Distribution of adenylyl cyclase/cAMP phosphodiesterase gene, CAPE, in streptophytes reproducing via motile sperm

Abstract

We recently isolated a novel adenylyl cyclase/cAMP phosphodiesterase gene from the liverwort, Marchantia polymorpha. The protein encoded by this gene has a class III adenylyl cyclase (AC) in the C-terminal domain and class I phosphodiesterase (PDE) in the N-terminal domain; therefore, we named it CAPE (COMBINED AC with PDE). CAPE protein is likely involved in spermatogenesis and sperm motility due to its tissue-specific expression pattern in M. polymorpha and the distribution of CAPE genes in streptophytes. However, little is known about the distribution of CAPE in gymnosperms that use motile sperm for fertilization, such as cycads and ginkgo. The present study aimed to isolate CAPE genes from the cycad, Cycas revoluta, the ginkgo, Ginkgo biloba, and the hornwort, Anthoceros agerestis. Sequences with high homology to CAPE were obtained from these species. Our analyses revealed that all plant taxonomic groups reproducing via motile sperm possessed CAPE, whereas those that do not produce motile sperm did not possess CAPE, with one exception in gymnosperm Cupressales. The phylogenic distribution of CAPE almost corresponds to the evolutionary history of motile sperm production and further suggests that CAPE may be involved in sexual reproduction process using motile sperm in streptophytes.

New Horizons in Plant Cell Signaling

“…While the generating enzymes of cyclic mononucleotides are being increasingly characterized, the degrading enzymes, the phosphodiesterases (PDEs), have remained elusive in vascular plants until recently. Previously, a novel protein harboring both AC and PDE activities known as CAPE (COMBINED AC with PDE) that may be involved in spermatogenesis and sperm motility, has been identified in the liverwort Marchantia polymorpha [ 36 , 37 ]. Adopting a motif-based approach similar to the one mentioned above, Kwiatkowski et al, 2021 [ 38 ] reported that a monocot Brachypodium distachyon (BdPDE1) can hydrolyze cNMPs to 5′NMPs but with a preference for cAMP over cGMP.…”