Proline-rich domains

These cytosolic proteins contain five EF-hand domains and are able to translocate to the plasma membrane upon calcium binding [5]. In addition to the EF-hand domains, these proteins also have a hydrophobic glycine/proline-rich domain, important for their translocation to the membrane. To date five members of this... 

CaMK kinases are Ca2+/calmodulin regulated kinases, while CMGC Pks collect cyclic-dependent, mitogene-activated peptide (MAP) kinases, GSK3 and Clk kinases, that phosphorylate substrates in proline-rich domains. The last group are PTKs (protein tyrosine kinases), which include both receptor and non-receptor kinases, which phosphorylates tyrosine residues (this will be discussed in Sect. 4.3). 

Blake, T. J., M. Shapiro, H. C. d. Morse, and W. Y. Langdon. The sequences of the human and mouse c-cbl proto-oncogenes show v-cbl was generated by a large truncation encompassing a proline-rich domain and a leucine zipper-like motif Oncogene. 6 653-657.1991. 

The activation of the Bt-kinase is a variation of the same theme phosphorylation of a Tyr, (Tyrl80), in the SH3 domain of the Bt-kinase relieves the blockade by interrupting the intramolecular interaction of the catalytic domain with the proline-rich (TH) domain, leading to activation. Moreover, several substrates of Src kinases have proline-rich domains which recognize SH3 domains and could de-inhibit the kinase. 

In platelets, signaling is initiated primarily through members of the heterotrimeric G protein-coiqtled femily of leceptois (seven transmembrane domains) and through adhesion receptors, and the signaling involves activation of both Ser/Thr kinases and tyrosine kinases. Neither G protein-coiqtled receptors nor adhesion receptors have intrinsic tyrosine kinase activity. However, NRTKs (with SH2-, SH3-, and proline-rich domains) are activated and initiate tyrosine phosphorylation reactions that in turn lead to the recmitment of signaling molecules to certain locations in the cell. These tyrosine kinases may phosphorylate submembranous proteins including receptors for cytoplasmic domains or components of the submembranous cytoskeleton of adhesion receptor-cytoskeleton... 

Each frustulin contains at least three of five structural elements 1) presequence domain, 2) acidic cysteine-rich domain with a highly repetitive structure, its common sequence being C-E/Q-G-D-C-D, 3) proline-rich domains, 4) polyglycine domains and 5) a tryptophan-rich domain. 

Examples of other trans-activating domains are the glutamine-rich domains of the transcription factor Spl and the proline-rich domain of the transcription factor CTF/ NF1, which contains 20% proline residues. 

The major domains of p53 characterized as transcriptional activation (TA), proline-rich domain (PRD), DNA-binding domain (DBD), nuclear localization signal (NLS), and carboxy-terminal domain (CTD). 

Furthermore, three well-defined domains have been identified in FAAH i) a transmembrane domain at the N-terminus which directs protein oligomerization, ii) a serine- and glycine-rich domain, and iii) a proline-rich domain. 

Fig. 8. Schematic representation of the apo BlOO molecule on an LDL particle [14]. The lipids are organized in an oil-drop model (cf. Fig. 7) and the elements of apo BlOO secondary structure on the particle are depicted. The N-terminal globular domain formed by lipovitellin-like structure is shown at the top of the diagram. The remaining secondary structure is a cartoon representation of the pentapartite model of apo BlOO (prd = proline rich domain).

A proline-rich domain is seen in the activator CTF-1. It has a domain of 84 amino acids, 19 of which are prolines. GTF-1 is a member of a class of transcription factors that bind to an extended promoter element called a GGAAT box. The N-terminal domain has been shown to regulate transcrip)-tion of certain genes. The G-terminal end is a transcription regulator and is known to bind to histone proteins via the proline repeats. An active area of study is how transcription is linked to the acetylation of histones. The coactivator GBP, which was discussed in the previous section, is also a histone acetyl transferase. See the article by Struhl cited in the bibliography at the end of this chapter. 

Many protein-protein binding domains also have identifiable motifs, such as acidic domains, glutamine-rich domains, and proline-rich domains. 

Acidic domains, glutamine-rich domains, and proline-rich domains. 

Grabs, D., Slepnev, V I., Songyang, Z., David, G., Lynch, M., Cantley, L. C., and De Camilli, P. (1997). The SHS domain of amphiphysin binds the proline-rich domain of dynamin at a single site that defines a new SHS binding consensus sequence. /. Biol. Chem. 272, 13419-13425. 

Domingo Kohler S, Weber A, Howard SP, Welte W, Drescher M (2010) The proline-rich domain of TonB possesses an extended polyproline Il-like conformation of sufficient length to span the periplasm of Gram-negative bacteria. Prot Sci 19 625-630... 

Skare P, Kreivi JP, Bergstrom A, Karlsson R (2003) Profilin I colocalizes with speckles and Cajal bodies a possible role in pre-mRNA splicing. Exp Cell Res 286 12-21 Solomaha E, Szeto FL, Yousef MA, Palfrey HC (2005) Kinetics of Src homology 3 domain association with the proline-rich domain of dynamins specificity, occlusion, and the effects of phosphorylation. J Biol Chem 280 23147-23156... 

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