Gene Ontology annotation through association of InterPro records with GO terms

Annotation inferences using phylogenetic trees

Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt

PMID:12826013

The Dictyostelium class I myosin, MyoD, contains a novel light chain that lacks high-affinity calcium-binding sites.

MlcD is a 16 kDa calmodulin-like protein that co-purifies with MyoD as two copies per heavy chain.

"MyoD, a long-tailed class I myosin, co-purified with two copies of a 16 kDa light chain"
MlcD has four EF-hands but only retains low-affinity calcium binding due to degenerate calcium-coordinating residues in EF-hands 2-4.

"MlcD comprises four EF-hands; however, EF-hands 2-4 contain mutations in key Ca2+-co-ordinating residues that would be predicted to impair Ca2+ binding"
MlcD binds calcium with a Kd of 52 uM, far above physiological calcium concentrations.

"yielding apparent dissociation constants ( K'(d)) of 52 microM for Ca2+ and 450 microM for Mg2+"
MlcD cannot function as a physiological calcium sensor.

"The low affinity of MlcD for Ca2+ indicates that it cannot function as a sensor of physiological Ca2+"
MlcD binding to MyoD is calcium-insensitive.

"Ca2+ did not affect the binding of MlcD to MyoD or to either of the two MyoD IQ (Ile-Gln) motifs"
MlcD specifically associates with MyoD and not with MyoB or MyoC.

"FLAG-MlcD expressed in Dictyostelium formed a complex with MyoD, but not with the two other long-tailed Dictyostelium myosin I isoenzymes, MyoB and MyoC"

PMID:16415352

Identification and characterization of an 8-kDa light chain associated with Dictyostelium discoideum MyoB, a class I myosin.

MlcB is a distinct light chain for MyoB, confirming that each long-tailed myosin I has a unique light chain partner.

"FLAG-MlcB expressed in Dictyostelium co-immunoprecipitated with MyoB but not with the related class myosins and MyoD"

PMID:21671662

Identification of calmodulin and MlcC as light chains for Dictyostelium myosin-I isozymes.

Each long-tailed Dictyostelium myosin I has a unique light chain, while short-tailed ones use calmodulin.

"Each long-tailed Dictyostelium myosin-I has now been shown to have a unique light chain (MyoB-MlcB, MyoC-MlcC, and MyoD-MlcD), whereas the short-tailed myosins-I, MyoA and MyoE, have the multifunctional calmodulin as a light chain"
Light chain diversity contributes to functional specialization of myosin I isoforms.

"The diversity in light chain composition is likely to contribute to the distinct cellular functions of each myosin-I isozyme"

PMID:31774725

Basic-hydrophobic sites are localized in conserved positions inside and outside of PH domains and affect localization of Dictyostelium myosin 1s.

Myo1D localizes to the PIP3-rich region inside actin waves, distinct from Myo1B which colocalizes with the actin wave itself.

"Myo1D localized, like short-tail Myo1E and Myo1F, in the PIP3-rich region encircled by the actin wave"
Myo1D localizes to macropinocytic cups and freshly internalized vesicles.

"Myo1D is also found in pinocytic protrusions and cups, and freshly internalized vesicles"