Implementing interface causes TPT where as inheriting from class causes TPH - ef-code-first

Question

I want to create a self referencing folder table , and related file table
As shown by MyFolder1 and MyFile1.
I understand how to get this structure by inheriting from an interface.
Can it also be achieved by inheriting from an abstract class?
public class Model1Context : DbContext
{
public Model1Context()
: base("name=Model1")
{
Database.SetInitializer(new Model1Initializer());
}
public virtual DbSet<MyFolder1> MyFolder1s { get; set; }
public virtual DbSet<MyFile1> MyFile1s { get; set; }
public virtual DbSet<MyFolder2> MyFolder2s { get; set; }
public virtual DbSet<MyFile2> MyFile2s { get; set; }
}
public class Model1Initializer : DropCreateDatabaseIfModelChanges<Model1Context>
{
}
public class MyFolder1 : BasicBO, ISequencedTreeNode
{
public MyFolder1 MyFolder { get; set; }
public int SeqNo { get; set; }
[NotMapped]
public ISequencedTreeNode Parent
{
get
{
return MyFolder;
}
set
{
MyFolder = (MyFolder1)value;
}
}
}
public class MyFile1 : BasicBO, ISequencedTreeNode
{
public MyFolder1 MyFolder { get; set; }
public int SeqNo { get; set; }
[NotMapped]
public ISequencedTreeNode Parent
{
get
{
return MyFolder;
}
set
{
MyFolder = (MyFolder1)value;
}
}
}
public interface ISequencedTreeNode
{
[Required]
int SeqNo { get; set; }
ISequencedTreeNode Parent { get; set; }
}
public abstract class SequencedTreeNode : BasicBO
{
[Required]
public int SeqNo { get; set; }
public SequencedTreeNode Parent { get; set; }
}
// [Table("MyFolder2")]
public class MyFolder2 : SequencedTreeNode
{
}
// [Table("MyFile2")]
public class MyFile2 : SequencedTreeNode
{
}
public class BasicBO
{
public int Id { get; set; }
public string Name { get; set; }
}
Marking BasicBO as abstract does not seem to affect the table construction.
[Update]
I can force TPT by adding a [Table('tablename')] attribute to MyFile2 and MyFolder2, however these tables will have a single Id field and the SequencedTreeNodes table will still create.
It makes sense to me that an interface may be more effective in forcing TPT since properties always need to be implemented for an interface. However I would have thought the same thing would happen if I made all the properties inside the SequencedTreeNode abstract. However If I do this I get a runtime error 'The property 'SeqNo' is not a declared property on type 'MyFile2''