We have isolated and sequenced two gamma-tubulin (gamma-Tub)-encoding macronuclear genes of the ciliate Euplotes crassus (Ec), as well as their corresponding cDNAs. Our results reveal that the two genes (gamma-tub 1 and gamma-tub 2) have introns in homologous positions, but differ in their sequences, codon usage, transcription initiation sites and poly(A) addition sites. They both consist of three exons, two introns and two short non-coding sequences on both ends, and they both code for polypeptides of 462 amino acids (aa). The two genes share 76% identity at the nucleotide (nt) level, 86% at the deduced aa level and show 61-92% aa homology to the gamma-Tubs of other organisms. The gamma-tub 2 gene contains two in-frame UGA codons which, like UGA codons in other Euplotes genes, probably code for cysteines. No UGA triplet was found in the gamma-tub 1 gene. Further studies on the cDNA ends indicate that gamma-tub 1 uses at least three transcription initiation sites and two poly(A) addition sites. In contrast, only one transcription initiation site and one poly(A) addition site were identified in gamma-tub 2.

Download full-text PDF

Source
http://dx.doi.org/10.1016/s0378-1119(98)00068-7DOI Listing

Publication Analysis

Top Keywords

transcription initiation
16
polya addition
16
initiation sites
12
sites polya
12
addition sites
12
genes ciliate
8
ciliate euplotes
8
euplotes crassus
8
differ sequences
8
sequences codon
8

Similar Publications

Role of polyamines in intestinal mucosal barrier function.

Semin Immunopathol

January 2025

Dairy Science and Technology Institute, Kyodo Milk Industry Co. Ltd, 20-1 Hirai, Hinode-Machi, Nishitama-Gun, Tokyo, 190-0182, Japan.

The intestinal epithelium is a rapidly self-renewing tissue; the rapid turnover prevents the invasion of pathogens and harmful components from the intestinal lumen, preventing inflammation and infectious diseases. Intestinal epithelial barrier function depends on the epithelial cell proliferation and junctions, as well as the state of the immune system in the lamina propria. Polyamines, particularly putrescine, spermidine, and spermine, are essential for many cell functions and play a crucial role in mammalian cellular homeostasis, such as that of cell growth, proliferation, differentiation, and maintenance, through multiple biological processes, including translation, transcription, and autophagy.

View Article and Find Full Text PDF

Ice plant (Mesembryanthemum crystallinum L.) is a halophyte and an inducible CAM plant. Ice plant seedlings display moderate salt tolerance, with root growth unaffected by 200 mM NaCl treatments, though hypocotyl elongation is hindered in salt-stressed etiolated seedlings.

View Article and Find Full Text PDF

Cell proliferation suppressor RBR1 interacts with ARID1 to promote pollen mitosis via stabilizing DUO1 in Arabidopsis.

New Phytol

January 2025

State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, 200438, China.

In plants, sperm cell formation involves two rounds of pollen mitoses, in which the microspore initiates the first pollen mitosis (PMI) to produce a vegetative cell and a generative cell, then the generative cell continues the second mitosis (PMII) to produce two sperm cells. DUO1, a R2R3 Myb transcription factor, is activated in the generative cell to promote S-G2/M transition during PMII. Loss-of-function of DUO1 caused a complete arrest of PMII.

View Article and Find Full Text PDF

Non-Canonical TERT Activity Initiates Osteogenesis in Calcific Aortic Valve Disease.

Circ Res

January 2025

Division of Cardiology, Department of Medicine, Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, PA. (R.A.C., C.C.C., R.W., A.C., C.B., C.R., W.J.M., M.J. Bashline, A.P., A.M.P., P.B., M.J. Brown, C.S.H.).

Background: Calcific aortic valve disease is the pathological remodeling of valve leaflets. The initial steps in valve leaflet osteogenic reprogramming are not fully understood. As TERT (telomerase reverse transcriptase) overexpression primes mesenchymal stem cells to differentiate into osteoblasts, we investigated whether TERT contributes to the osteogenic reprogramming of valve interstitial cells.

View Article and Find Full Text PDF

and mRNA expression-based risk stratification of acute Myeloid Leukemia.

Leuk Res Rep

December 2024

Independent Researcher, Gimpo-si, Gyeonggi-do 10090, South Korea.

Prognostication of acute myeloid leukemia (AML) at initial diagnosis relies on identification of pre-determined underlying genetic abnormalities. Nevertheless, the disease course of AML remains highly unpredictable and robust reliable prognostic biomarkers for newly diagnosed AML are lacking. We retrospectively explored two publicly available AML RNA-Seq datasets and found that inferior overall survival was associated with high- and low- transcript levels (" / ") compared to low- and high- transcript levels (" / ") in adult AML patients, with a hazard ratio for death of at least 2.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!