What kind of structure does influenza have?
The influenza particle, or virion, is typically spherical, but sometimes filamentous. It has an outer lipid membrane layer called an envelope derived from the host cell that it replicated in. The envelope is covered with glycoproteins HA and NA which form structures like spikes.
What is the main shape of the influenza virus?
The influenza virion (as the infectious particle is called) is roughly spherical. It is an enveloped virus – that is, the outer layer is a lipid membrane which is taken from the host cell in which the virus multiplies.
Is influenza single or double stranded?
All influenza viruses consist of single-stranded RNA as opposed to dual-stranded DNA. The RNA genes of influenza viruses are made up of chains of nucleotides that are bonded together and coded by the letters A, C, G and U, which stand for adenine, cytosine, guanine, and uracil, respectively.
What are the unique characteristics of influenza virus?
The physical characteristics of influenza viruses are that they are single-stranded, RNA viruses enclosed in a helical nucleocapsid. On the outside, these viruses are enveloped. Two important proteins are found on surface of this envelope: hemagglutinin and neurominidase.
Is influenza virus shape?
VIRION STRUCTURE AND ORGANIZATION By electron microscopy, influenza A and B viruses are virtually indistinguishable. They are spherical or filamentous in shape, with the spherical forms on the order of 100 nm in diameter and the filamentous forms often in excess of 300 nm in length.
Is influenza A icosahedral virus?
The most well-known examples of enveloped viruses are the influenza virus, Hepatitis C and HIV.
What disease does influenza cause?
Complications of flu can include bacterial pneumonia, ear infections, sinus infections and worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes.
Is flu virus an RNA virus?
Genome. Coronaviruses and influenza viruses are both enveloped, single-stranded RNA viruses, and both are encapsidated by nucleoprotein. However, the genomes of these 2 viruses differ in polarity and segmentation. Influenza virus is comprised of 8 single-stranded negative-sense, viral RNA segments.
Is influenza ssRNA or dsRNA?
The nucleic acid is usually single-stranded RNA (ssRNA) but it may be double-stranded RNA (dsRNA). Notable human diseases caused by RNA viruses include the common cold, influenza, SARS, MERS, COVID-19, Dengue Virus, hepatitis C, hepatitis E, West Nile fever, Ebola virus disease, rabies, polio, mumps, and measles.
What other viruses can cause influenza?
Influenza A and B viruses are the most common causes of influenza-like illness (ILI), but other pathogens also cause ILI, including influenza C viruses, parainfluenza viruses, respiratory syncytial viruses, and Mycoplasma pneumoniae.
Is flu a DNA or RNA virus?
Coronaviruses and influenza viruses are both enveloped, single-stranded RNA viruses, and both are encapsidated by nucleoprotein. However, the genomes of these 2 viruses differ in polarity and segmentation. Influenza virus is comprised of 8 single-stranded negative-sense, viral RNA segments.
What is the structure of an influenza virus?
Structure and genetics. Influenza type A viruses are very similar in structure to influenza viruses types B, C, and D. The virus particle (also called the virion) is 80–120 nanometers in diameter such that the smallest virions adopt an elliptical shape.
How many genes does the influenza virus have?
It is an enveloped virus with a negative sense RNA segmented genome that encodes for 11 viral genes. This virus has evolved a number of mechanisms that enable it to invade host cells and subvert the host cell machinery for its own purpose, that is, for the sole production of more virus.
What is the function of NP in influenza A?
The influenza A virus NP is a multifunctional protein that has been shown to interact with a number of viral (e.g. PB1, PB2, M1, etc.) and host proteins (e.g. RAF-2p48/UAP56 and Tat-SF1, etc.) . One of the NP’s primary functions is to coat viral RNA to facilitate its folding into a double-helical RNP structure.
What’s the difference between influenza A and C viruses?
The genomic organization of influenza C viruses is generally similar to that of influenza A and B viruses; however, the HEF protein of influenza C replaces the HA and NA proteins, and thus the influenza C virus genome has one fewer segment than that of influenza A or B viruses.