Phosphatase Subfamily Dullard

Introduction

Dullard, is also known as CTDNEP1 (CTD nuclear envelope phosphatase 1). It participates in a unique phosphatase cascade regulating nuclear membrane biogenesis, and the cascade is conserved from yeast to human [1] (in particular, Figure 5B). Dullard, as well as its substrate, phosphatidic acid phosphatase, lipin, is conserved from yeast to human.

Substrates and Related Kinases

	Phosphatase	Lipin	Kinase
Yeast	Nem1-Spo7 complex	Smp2	Cdc28/Cdk1
Mammals	Dullard (-? complex)	LIPIN	mTOR

Note: i) The kinases are of different families in yeast and mammals, though both of them are conserved from yeast to human. (The tree of the family containing yeast Cdc28 may be wrong is KinBase). ii) Dullard may have a unknown partner.

1. Cdc28/Cdk1 (in yeast). Smp2 is phosphorylated by Cdc28/Cdk1 and dephosphorylated by a nuclear/endoplasmic reticulum (ER) membrane-localized CPD phosphatase complex consisting of Nem1 and Spo7 [2].

2. mTOR (in mammals). Lipin has multiple phosphorylation sites. Though many kinases may involve in the multisite phosphorylation, mTOR plays an important role [3].

Evolutionary History

Dullard is conserved from yeast to human, so is its substrate lipin and the kinases phosphorylating lipin. However, interestingly, the kinases in yeast and mammals are of different families, though both of them are present in yeast and mammals. It is quite interesting that the same molecular function are carried out by different protein families in yeast and mammals.

References

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Links

Human Dullard from NCBI Gene