A functional heme-binding site of soluble guanylyl cyclase requires intact N-termini of alpha 1 and beta 1 subunits.

Soluble guanylyl cyclase, a heterodimeric enzyme, is the most important intracellular target for the signalling molecule nitric oxide (NO). NO stimulates the enzyme by binding to a prosthetic heme group. The identity of the axial heme ligand, however, is still unknown.

Mutation of His-105 in the beta 1 subunit yields a nitric oxide-insensitive form of soluble guanylyl cyclase.

Soluble guanylyl cyclase [GTP pyrophosphate-lyase (cyclizing); EC 4.6.1.

Molecular cloning and expression of a new alpha-subunit of soluble guanylyl cyclase. Interchangeability of the alpha-subunits of the enzyme.

A cDNA coding for a new subunit of soluble guanylyl cyclase with a calculated molecular mass of 81.7 kDa was cloned and sequenced. On the basis of sequence homology, the new subunit appears to be an isoform of the alpha 1-subunit and was designated alpha 2 as the new subunit is very similar to the alpha 1-subunit in the middle and C-terminal part; it is quite diverse in the N-terminal part.

Glucose transporter in plasma membranes of cultured neural cells, as characterized by cytochalasin B binding.

Identification of hexose transporter sites by cytochalasin B binding was conducted with a centrifugation assay. The determination of KD and Bmax values by LIGAND computer analysis provided binding data that are similar in primary astrocytes (238 nM and 14 pmol/mg protein) and neuroblastoma cells (179 nM and 13.6 pmol/mg protein).